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Computer Security and Mobile Security Challenges



Computer security, also known as cybersecurity or IT security, is the protection of information systems from theft or damage to the hardware, the software, and to the information on them, as well as from disruption or misdirection of the services they provide. [1] It includes controlling physical access to the hardware, as well as protecting against harm that may come via network access, data and code injection, [2] and due to malpractice by operators, whether intentional, accidental, or due to them being tricked into deviating from secure procedures. [3] The field is of growing importance due to the increasing reliance on computer systems in most societies. [4] Computer systems now include a very wide variety of "smart" devices, including smartphones, televisions and tiny devices as part of the Internet of Things – and networks include not only the Internet and private data networks, but also Bluetooth, Wi-Fi and other wireless networks. Vulnerabilities and attacks A vulnerability is a system susceptibility or flaw, and many vulnerabilities are documented in the Common Vulnerabilities and Exposures (CVE) database and vulnerability management is the cyclical practice of identifying, classifying, remediating, and mitigating vulnerabilities as they are discovered. An exploitable vulnerability is one for which at least one working attack or "exploit" exists. To secure a computer system, it is important to understand the attacks that can be made against it, and these threats can typically be classified into one of the categories below: Backdoors A backdoor in a computer system, a cryptosystem or an algorithm, is any secret method of bypassing normal authentication or security controls. They may exist for a number of reasons, including by original design or from poor configuration. They may also have been added later by an authorized party to allow some legitimate access, or by an attacker for malicious reasons; but regardless of the motives for their existence, they create a vulnerability. Denial-of-service attack Denial of service attacks are designed to make a machine or network resource unavailable to its intended users. Attackers can deny service to individual victims, such as by deliberately entering a wrong password enough consecutive times to cause the victim account to be locked, or they may overload the capabilities of a machine or network and block all users at once. While a network attack from a single IP address can be blocked by adding a new firewall rule, many forms of Distributed denial of service (DDoS) attacks are possible, where the attack comes from a large number of points – and defending is much more difficult. Such attacks can originate from the zombie computers of a botnet, but a range of other techniques are possible including reflection and amplification attacks, where innocent systems are fooled into sending traffic to the victim.
Computer Security and Mobile Security Challenges
Nikola Zlatanov*
Computer security, also known as cybersecurity or IT security, is the protection of information
systems from theft or damage to the hardware, the software, and to the information on them, as well
as from disruption or misdirection of the services they provide.[1] It includes controlling physical
access to the hardware, as well as protecting against harm that may come via network access, data
and code injection,[2] and due to malpractice by operators, whether intentional, accidental, or due to
them being tricked into deviating from secure procedures.[3]
The field is of growing importance due to the increasing reliance on computer systems in most
societies.[4] Computer systems now include a very wide variety of "smart" devices,
including smartphones, televisions and tiny devices as part of the Internet of Thingsand networks
include not only the Internet and private data networks, but also Bluetooth, Wi-Fi and other wireless
Vulnerabilities and attacks
A vulnerability is a system susceptibility or flaw, and many vulnerabilities are documented in
the Common Vulnerabilities and Exposures (CVE) database and vulnerability management is the
cyclical practice of identifying, classifying, remediating, and mitigating vulnerabilities as they are
discovered. An exploitable vulnerability is one for which at least one working attack or "exploit" exists.
To secure a computer system, it is important to understand the attacks that can be made against it, and
these threats can typically be classified into one of the categories below:
A backdoor in a computer system, a cryptosystem or an algorithm, is any secret method of bypassing
normal authentication or security controls. They may exist for a number of reasons, including by original
design or from poor configuration. They may also have been added later by an authorized party to allow
some legitimate access, or by an attacker for malicious reasons; but regardless of the motives for their
existence, they create a vulnerability.
Denial-of-service attack
Denial of service attacks are designed to make a machine or network resource unavailable to its
intended users. Attackers can deny service to individual victims, such as by deliberately entering a wrong
password enough consecutive times to cause the victim account to be locked, or they may overload the
capabilities of a machine or network and block all users at once. While a network attack from a single IP
address can be blocked by adding a new firewall rule, many forms of Distributed denial of service
(DDoS) attacks are possible, where the attack comes from a large number of points and defending is
much more difficult. Such attacks can originate from the zombie computers of a botnet, but a range of
other techniques are possible including reflection and amplification attacks, where innocent systems
are fooled into sending traffic to the victim.
Direct-access attacks
An unauthorized user gaining physical access to a computer is most likely able to directly download data
from it. They may also compromise security by making operating system modifications, installing
software worms, keyloggers, or covert listening devices. Even when the system is protected by
standard security measures, these may be able to be bypassed by booting another operating system or
tool from a CD-ROM or other bootable media. Disk encryption and Trusted Platform Module are
designed to prevent these attacks.
Eavesdropping is the act of surreptitiously listening to a private conversation, typically between hosts on
a network. For instance, programs such as Carnivore and NarusInsight have been used by the FBI
and NSA to eavesdrop on the systems of internet service providers. Even machines that operate as a
closed system (i.e., with no contact to the outside world) can be eavesdropped upon via monitoring the
faint electro-magnetic transmissions generated by the hardware; TEMPEST is a specification by the
NSA referring to these attacks.
Spoofing of user identity describes a situation in which one person or program successfully
masquerades as another by falsifying data.
Tampering describes a malicious modification of products. So-called "Evil Maid" attacks and security
services planting of surveillance capability into routers[5] are examples.
Privilege escalation
Privilege escalation describes a situation where an attacker with some level of restricted access is able
to, without authorization, elevate their privileges or access level. So for example, a standard computer
user may be able to fool the system into giving them access to restricted data; or even to "become root"
and have full unrestricted access to a system.
Phishing is the attempt to acquire sensitive information such as usernames, passwords, and credit card
details directly from users. Phishing is typically carried out by email spoofing or instant messaging, and it
often directs users to enter details at a fake website whose look and feel are almost identical to the
legitimate one. Preying on a victim's trusting, phishing can be classified as a form of social engineering.
Clickjacking, also known as "UI redress attack or User Interface redress attack", is a malicious
technique in which an attacker tricks a user into clicking on a button or link on another webpage while the
user intended to click on the top level page. This is done using multiple transparent or opaque layers.
The attacker is basically "hijacking" the clicks meant for the top level page and routing them to some
other irrelevant page, most likely owned by someone else. A similar technique can be used to hijack
keystrokes. Carefully drafting a combination of stylesheets, iframes, buttons and text boxes, a user can
be led into believing that they are typing the password or other information on some authentic webpage
while it is being channeled into an invisible frame controlled by the attacker.
Social engineering and Trojans
Social engineering aims to convince a user to disclose secrets such as passwords, card numbers, etc.
by, for example, impersonating a bank, a contractor, or a customer.[6]
Systems at risk
Computer security is critical in almost any industry which uses computers.[7]
Financial systems
Web sites that accept or store credit card numbers and bank account information are prominent hacking
targets, because of the potential for immediate financial gain from transferring money, making
purchases, or selling the information on the black market. In-store payment systems and ATMs have
also been tampered with in order to gather customer account data and PINs.
Utilities and industrial equipment
Computers control functions at many utilities, including coordination of telecommunications, the power
grid, nuclear power plants, and valve opening and closing in water and gas networks. The Internet is a
potential attack vector for such machines if connected, but the Stuxnet worm demonstrated that even
equipment controlled by computers not connected to the Internet can be vulnerable to physical damage
caused by malicious commands sent to industrial equipment (in that case uranium enrichment
centrifuges) which are infected via removable media. In 2014, the Computer Emergency Readiness
Team, a division of the Department of Homeland Security, investigated 79 hacking incidents at energy
The aviation industry is very reliant on a series of complex system which could be attacked.[9] A simple
power outage at one airport can cause repercussions worldwide,[10] much of the system relies on radio
transmissions which could be disrupted,[11] and controlling aircraft over oceans is especially dangerous
because radar surveillance only extends 175 to 225 miles offshore.[12] There is also potential for attack
from within an aircraft.[13]
The consequences of a successful attack range from loss of confidentiality to loss of system integrity,
which may lead to more serious concerns such as exfiltration of data, network and air traffic control
outages, which in turn can lead to airport closures, loss of aircraft, loss of passenger life, damages on
the ground and to transportation infrastructure. A successful attack on a military aviation system that
controls munitions could have even more serious consequences.
Consumer devices
Desktop computers and laptops are commonly infected with malware either to gather passwords or
financial account information, or to construct a botnet to attack another target. Smart phones, tablet
computers, smart watches, and other mobile devices such as Quantified Self devices like activity
trackers have also become targets and many of these have sensors such as cameras, microphones,
GPS receivers, compasses, and accelerometers which could be exploited, and may collect personal
information, including sensitive health information. Wi-Fi, Bluetooth, and cell phone network on any of
these devices could be used as attack vectors, and sensors might be remotely activated after a
successful breach.[14] Home automation devices such as the Nest thermostat are also potential
Large corporations
Large corporations are common targets. In many cases this is aimed at financial gain through identity
theft and involves data breaches such as the loss of millions of clients' credit card details by Home
Depot,[15] Staples,[16] and Target Corporation.[17]
Not all attacks are financially motivated however; for example security firm HBGary Federal suffered a
serious series of attacks in 2011 from hacktivist group Anonymous in retaliation for the firm's CEO
claiming to have infiltrated their group, [18][19] and Sony Pictures was attacked in 2014 where the motive
appears to have been to embarrass with data leaks, and cripple the company by wiping workstations and
If access is gained to a car's internal controller area network, it is possible to disable the brakes and turn
the steering wheel.[22] Computerized engine timing, cruise control, anti-lock brakes, seat belt tensioners,
door locks, airbags and advanced driver assistance systems make these disruptions possible,
and self-driving cars go even further. Connected cars may use Wi-Fi and Bluetooth to communicate
with onboard consumer devices, and the cell phone network to contact concierge and emergency
assistance services or get navigational or entertainment information; each of these networks is a
potential entry point for malware or an attacker.[22] Researchers in 2011 were even able to use a
malicious compact disc in a car's stereo system as a successful attack vector,[23] and cars with built-in
voice recognition or remote assistance features have onboard microphones which could be used for
A 2015 report by U.S. Senator Edward Markey criticized manufacturers' security measures as
inadequate, and also highlighted privacy concerns about driving, location, and diagnostic data being
collected, which is vulnerable to abuse by both manufacturers and hackers.[24]
Government and military computer systems are commonly attacked by activists[25][26][27][28] and foreign
powers.[29][30][31][32] Local and regional government infrastructure such as traffic light controls, police and
intelligence agency communications, personnel records and financial systems are also potential targets
as they are now all largely computerized.
Impact of security breaches
Serious financial damage has been caused by security breaches, but because there is no standard
model for estimating the cost of an incident, the only data available is that which is made public by the
organizations involved. "Several computer security consulting firms produce estimates of total worldwide
losses attributable to virus and worm attacks and to hostile digital acts in general. The 2003 loss
estimates by these firms range from $13 billion (worms and viruses only) to $226 billion (for all forms of
covert attacks). The reliability of these estimates is often challenged; the underlying methodology is
basically anecdotal."[33]
However, reasonable estimates of the financial cost of security breaches can actually help organizations
make rational investment decisions. According to the classic Gordon-Loeb Model analyzing the optimal
investment level in information security, one can conclude that the amount a firm spends to protect
information should generally be only a small fraction of the expected loss (i.e., the expected value of the
loss resulting from a cyber/information security breach).[34]
Attacker motivation
As with physical security, the motivations for breaches of computer security vary between attackers.
Some are thrill-seekers or vandals, others are activists or criminals looking for financial gain. State-
sponsored attackers are now common and well resourced, but started with amateurs such as Markus
Hess who hacked for the KGB, as recounted by Clifford Stoll, in The Cuckoo's Egg.
A standard part of threat modelling for any particular system is to identify what might motivate an attack
on that system, and who might be motivated to breach it. The level and detail of precautions will vary
depending on the system to be secured. A home personal computer, bank, and classified
military network face very different threats, even when the underlying technologies in use are similar.
Computer protection (countermeasures)
In computer security a countermeasure is an action, device, procedure, or technique that reduces
a threat, a vulnerability, or an attack by eliminating or preventing it, by minimizing the harm it can
cause, or by discovering and reporting it so that corrective action can be taken.[35][36][37]
Security measures
A state of computer "security" is the conceptual ideal, attained by the use of the three processes: threat
prevention, detection, and response. These processes are based on various policies and system
components, which include the following:
User account access controls and cryptography can protect systems files and data,
Firewalls are by far the most common prevention systems from a network security perspective as
they can (if properly configured) shield access to internal network services, and block certain kinds of
attacks through packet filtering. Firewalls can be both hardware- or software-based.
Intrusion Detection System (IDS) products are designed to detect network attacks in-progress
and assist in post-attack forensics, while audit trails and logs serve a similar function for individual
"Response" is necessarily defined by the assessed security requirements of an individual system
and may cover the range from simple upgrade of protections to notification of legal authorities, counter-
attacks, and the like. In some special cases, a complete destruction of the compromised system is
favored, as it may happen that not all the compromised resources are detected.
Today, computer security comprises mainly "preventive" measures, like firewalls or an exit procedure.
A firewall can be defined as a way of filtering network data between a host or a network and another
network, such as the Internet, and can be implemented as software running on the machine, hooking
into the network stack (or, in the case of most UNIX-based operating systems such as Linux, built into
the operating system kernel) to provide real time filtering and blocking. Another implementation is a so-
called physical firewall which consists of a separate machine filtering network traffic. Firewalls are
common amongst machines that are permanently connected to the Internet.
However, relatively few organizations maintain computer systems with effective detection systems, and
fewer still have organized response mechaniSMS in place. As result, as Reuters points out: "Companies
for the first time report they are losing more through electronic theft of data than physical stealing of
assets".[38] The primary obstacle to effective eradication of cybercrime could be traced to excessive
reliance on firewalls and other automated "detection" systems. Yet it is basic evidence gathering by
using packet capture appliances that puts criminals behind bars.
Reducing vulnerabilities
While formal verification of the correctness of computer systems is possible,[39][40] it is not yet common.
Operating systems formally verified include seL4,[41] and SYSGO's PikeOS[42][43]but these make up a
very small percentage of the market.
Cryptography properly implemented is now virtually impossible to directly break. Breaking them requires
some non-cryptographic input, such as a stolen key, stolen plaintext (at either end of the transmission),
or some other extra cryptanalytic information.
Two factor authentication is a method for mitigating unauthorized access to a system or sensitive
information. It requires "something you know"; a password or PIN, and "something you have"; a card,
dongle, cellphone, or other piece of hardware. This increases security as an unauthorized person needs
both of these to gain access.
Social engineering and direct computer access (physical) attacks can only be prevented by non-
computer means, which can be difficult to enforce, relative to the sensitivity of the information. Even in a
highly disciplined environment, such as in military organizations, social engineering attacks can still be
difficult to foresee and prevent.
It is possible to reduce an attacker's chances by keeping systems up to date with security patches and
updates, using a security scanner or/and hiring competent people responsible for security. The effects of
data loss/damage can be reduced by careful backing up and insurance.
Security by design
Security by design, or alternately secure by design, means that the software has been designed from
the ground up to be secure. In this case, security is considered as a main feature.
Some of the techniques in this approach include:
The principle of least privilege, where each part of the system has only the privileges that are
needed for its function. That way even if an attacker gains access to that part, they have only limited
access to the whole system.
Automated theorem proving to prove the correctness of crucial software subsystems.
Code reviews and unit testing, approaches to make modules more secure where formal
correctness proofs are not possible.
Defense in depth, where the design is such that more than one subsystem needs to be violated
to compromise the integrity of the system and the information it holds.
Default secure settings, and design to "fail secure" rather than "fail insecure". Ideally, a secure
system should require a deliberate, conscious, knowledgeable and free decision on the part of legitimate
authorities in order to make it insecure.
Audit trails tracking system activity, so that when a security breach occurs, the mechanism and
extent of the breach can be determined. Storing audit trails remotely, where they can only be appended
to, can keep intruders from covering their tracks.
Full disclosure of all vulnerabilities, to ensure that the "window of vulnerability" is kept as short
as possible when bugs are discovered.
Security architecture
The Open Security Architecture organization defines IT security architecture as "the design artifacts that
describe how the security controls (security countermeasures) are positioned, and how they relate to the
overall information technology architecture. These controls serve the purpose to maintain the system's
quality attributes: confidentiality, integrity, availability, accountability and assurance services".[44]
Techopedia defines security architecture as "a unified security design that addresses the necessities and
potential risks involved in a certain scenario or environment. It also specifies when and where to apply
security controls. The design process is generally reproducible." The key attributes of security
architecture are:[45]
the relationship of different components and how they depend on each other.
the determination of controls based on risk assessment, good practice, finances, and legal
the standardization of controls.
Hardware protection mechaniSMS
While hardware may be a source of insecurity, such as with microchip vulnerabilities maliciously
introduced during the manufacturing process,[46][47] hardware-based or assisted computer security also
offers an alternative to software-only computer security. Using devices and methods such
as dongles, trusted platform modules, intrusion-aware cases, drive locks, disabling USB ports, and
mobile-enabled access may be considered more secure due to the physical access (or
sophisticated backdoor access) required in order to be compromised. Each of these is covered in more
detail below.
USB dongles are typically used in software licensing schemes to unlock software capabilities,[48]
but they can also be seen as a way to prevent unauthorized access to a computer or other device's
software. The dongle, or key, essentially creates a secure encrypted tunnel between the software
application and the key. The principle is that an encryption scheme on the dongle, such as Advanced
Encryption Standard (AES) provides a stronger measure of security, since it is harder to hack and
replicate the dongle than to simply copy the native software to another machine and use it. Another
security application for dongles is to use them for accessing web-based content such as cloud software
or Virtual Private Networks (VPNs).[49] In addition, a USB dongle can be configured to lock or unlock a
Trusted platform modules (TPMs) secure devices by integrating cryptographic capabilities onto
access devices, through the use of microprocessors, or so-called computers-on-a-chip. TPMs used in
conjunction with server-side software offer a way to detect and authenticate hardware devices,
preventing unauthorized network and data access.[51]
Computer case intrusion detection refers to a push-button switch which is triggered when a
computer case is opened. The firmware or BIOS is programmed to show an alert to the operator when
the computer is booted up the next time.
Drive locks are essentially software tools to encrypt hard drives, making them inaccessible to
thieves.[52] Tools exist specifically for encrypting external drives as well.[53]
Disabling USB ports is a security option for preventing unauthorized and malicious access to an
otherwise secure computer. Infected USB dongles connected to a network from a computer inside the
firewall are considered by the magazine Network World as the most common hardware threat facing
computer networks.[54]
Mobile-enabled access devices are growing in popularity due to the ubiquitous nature of cell
phones. Built-in capabilities such as Bluetooth, the newer Bluetooth low energy (LE), Near field
communication (NFC) on non-iOS devices and biometric validation such as thumb print readers, as
well as QR code reader software designed for mobile devices, offer new, secure ways for mobile phones
to connect to access control systems. These control systems provide computer security and can also be
used for controlling access to secure buildings.[55]
Secure operating systems
One use of the term "computer security" refers to technology that is used to implement secure operating
systems. In the 1980s the United States Department of Defense (DoD) used the "Orange Book"[56]
standards, but the current international standard ISO/IEC 15408, "Common Criteria" defines a number
of progressively more stringent Evaluation Assurance Levels. Many common operating systems meet
the EAL4 standard of being "Methodically Designed, Tested and Reviewed", but the formal verification
required for the highest levels means that they are uncommon. An example of an EAL6 ("Semiformally
Verified Design and Tested") system is Integrity-178B, which is used in the Airbus A380[57] and several
military jets.[58]
Secure coding
In software engineering, secure coding aims to guard against the accidental introduction of security
vulnerabilities. It is also possible to create software designed from the ground up to be secure. Such
systems are "secure by design". Beyond this, formal verification aims to prove the correctness of
the algorithms underlying a system;[59] important for cryptographic protocols for example.
Capabilities and access control lists
Within computer systems, two of many security models capable of enforcing privilege separation
are access control lists (ACLs) and capability-based security. Using ACLs to confine programs has
been proven to be insecure in many situations, such as if the host computer can be tricked into indirectly
allowing restricted file access, an issue known as the confused deputy problem. It has also been
shown that the promise of ACLs of giving access to an object to only one person can never be
guaranteed in practice. Both of these problems are resolved by capabilities. This does not mean practical
flaws exist in all ACL-based systems, but only that the designers of certain utilities must take
responsibility to ensure that they do not introduce flaws.
Capabilities have been mostly restricted to research operating systems, while commercial OSs still use
ACLs. Capabilities can, however, also be implemented at the language level, leading to a style of
programming that is essentially a refinement of standard object-oriented design. An open source project
in the area is the E language.
The most secure computers are those not connected to the Internet and shielded from any interference.
In the real world, the most secure systems are operating systems where security is not an add-on.
Response to breaches
Responding forcefully to attempted security breaches (in the manner that one would for attempted
physical security breaches) is often very difficult for a variety of reasons:
Identifying attackers is difficult, as they are often in a different jurisdiction to the systems they
attempt to breach, and operate through proxies, temporary anonymous dial-up accounts, wireless
connections, and other anonymizing procedures which make backtracking difficult and are often located
in yet another jurisdiction. If they successfully breach security, they are often able to delete logs to cover
their tracks.
The sheer number of attempted attacks is so large that organizations cannot spend time pursuing
each attacker (a typical home user with a permanent (e.g., cable modem) connection will be attacked at
least several times per day, so more attractive targets could be presumed to see many more). Note
however, that most of the sheer bulk of these attacks are made by automated vulnerability scanners
and computer worms.
Law enforcement officers are often unfamiliar with information technology, and so lack the
skills and interest in pursuing attackers. There are also budgetary constraints. It has been argued that
the high cost of technology, such as DNA testing, and improved forensics mean less money for other
kinds of law enforcement, so the overall rate of criminals not getting dealt with goes up as the cost of the
technology increases. In addition, the identification of attackers across a network may require logs from
various points in the network and in many countries, the release of these records to law enforcement
(with the exception of being voluntarily surrendered by a network administrator or a system
administrator) requires a search warrant and, depending on the circumstances, the legal proceedings
required can be drawn out to the point where the records are either regularly destroyed, or the
information is no longer relevant.
Notable computer security attacks and breaches
Robert Morris and the first computer worm
In 1988, only 60,000 computers were connected to the Internet, and most were mainframes,
minicomputers and professional workstations. On November 2, 1988, many started to slow down,
because they were running a malicious code that demanded processor time and that spread itself to
other computers the first internet "computer worm".[60] The software was traced back to 23-year-
old Cornell University graduate student Robert Tappan Morris, Jr. who said 'he wanted to count how
many machines were connected to the Internet'.[60]
Rome Laboratory
In 1994, over a hundred intrusions were made by unidentified crackers into the Rome Laboratory, the
US Air Force's main command and research facility. Using Trojan horses, hackers were able to obtain
unrestricted access to Rome's networking systems and remove traces of their activities. The intruders
were able to obtain classified files, such as air tasking order systems data and furthermore able to
penetrate connected networks of NASA's Goddard Space Flight Center, Wright-Patterson Air Force
Base, some Defense contractors, and other private sector organizations, by posing as a trusted Rome
center user.[61]
TJX loses 45.7m customer credit card details
In early 2007, American apparel and home goods company TJX announced that it was the victim of
an unauthorized computer systems intrusion[62] and that the hackers had accessed a system that
stored data on credit card, debit card, check, and merchandise return transactions.[63]
Stuxnet attack
The computer worm known as Stuxnet reportedly ruined almost one-fifth of Iran's nuclear centrifuges[64]
by disrupting industrial programmable logic controllers (PLCs) in a targeted attack generally believed
to have been launched by Israel and the United States[65][66][67][68] although neither has publicly
acknowledged this.
Global surveillance disclosures
In early 2013, massive breaches of computer security by the NSA were revealed, including deliberately
inserting a backdoor in a NIST standard for encryption[69] and tapping the links between Google's data
centers.[70] These were disclosed by NSA contractor Edward Snowden.[71]
Target and Home Depot breaches
In 2013 and 2014, a Russian/Ukrainian hacking ring known as "Rescator" broke into Target
Corporation computers in 2013, stealing roughly 40 million credit cards,[72] and then Home Depot
computers in 2014, stealing between 53 and 56 million credit card numbers.[73] Warnings were delivered
at both corporations, but ignored; physical security breaches using self-checkout machines are believed
to have played a large role. "The malware utilized is absolutely unsophisticated and uninteresting," says
Jim Walter, director of threat intelligence operations at security technology company McAfee meaning
that the heists could have easily been stopped by existing antivirus software had administrators
responded to the warnings. The size of the thefts has resulted in major attention from state and Federal
United States authorities and the investigation is ongoing.
Ashley Madison breach
In July of 2015, a hacker group known as "The Impact Team" successfully breached the extramarital
relationship website Ashley Madison. The group claimed that they had taken not only company data but
user data as well. After the breach, The Impact Team dumped emails from the company's CEO, to prove
their point, and threatened to dump customer data unless the website was taken down permanently. With
this initial data release, the group stated “Avid Life Media has been instructed to take Ashley Madison
and Established Men offline permanently in all forms, or we will release all customer records, including
profiles with all the customers' secret sexual fantasies and matching credit card transactions, real names
and addresses, and employee documents and emails. The other websites may stay online.” [74] When
Avid Life Media, the parent company that created the Ashley Madison website, did not take the site
offline, The Impact Group released two more compressed files, one 9.7GB and the second 20GB. After
the second data dump, Avid Life Media CEO Noel Biderman resigned, but the website remained
Legal issues and global regulation
Conflict of laws in cyberspace has become a major cause of concern for computer security community.
Some of the main challenges and complaints about the antivirus industry are the lack of global web
regulations, a global base of common rules to judge, and eventually punish, cyber crimes and cyber
criminals. There is no global cyber law and cybersecurity treaty that can be invoked for enforcing global
cybersecurity issues.
International legal issues of cyber attacks are complicated in nature. Even if an antivirus firm locates the
cyber criminal behind the creation of a particular virus or piece of malware or form of cyber attack, often
the local authorities cannot take action due to lack of laws under which to prosecute.[75][76] Authorship
attribution for cyber crimes and cyber attacks is a major problem for all law enforcement agencies.
"[Computer viruses] switch from one country to another, from one jurisdiction to another moving
around the world, using the fact that we don't have the capability to globally police operations like this. So
the Internet is as if someone [had] given free plane tickets to all the online criminals of the world."[75] Use
of dynamic DNS, fast flux and bullet proof servers have added own complexities to this situation.
The role of the government is to make regulations to force companies and organizations to protect their
systems, infrastructure and information from any cyber attacks, but also to protect its own national
infrastructure such as the national power-grid.[77]
The question of whether the government should intervene or not in the regulation of the cyberspace is a
very polemical one. Indeed, for as long as it has existed and by definition, the cyberspace is a virtual
space free of any government intervention. Where everyone agree that an improvement on cybersecurity
is more than vital, is the government the best actor to solve this issue? Many government officials and
experts think that the government should step in and that there is a crucial need for regulation, mainly
due to the failure of the private sector to solve efficiently the cybersecurity problem. R. Clarke said during
a panel discussion at the RSA Security Conference in San Francisco, he believes that the "industry
only responds when you threaten regulation. If industry doesn't respond (to the threat), you have to
follow through."[78] On the other hand, executives from the private sector agree that improvements are
necessary, but think that the government intervention would affect their ability to innovate efficiently.
Actions and teams in the US
The 1986 18 U.S.C. § 1030, more commonly known as the Computer Fraud and Abuse Act is the key
legislation. It prohibits unauthorized access or damage of "protected computers" as defined in 18
U.S.C. § 1030(e)(2).
Although various other measures have been proposed, such as the "Cybersecurity Act of 2010 S. 773"
in 2009, the "International Cybercrime Reporting and Cooperation Act H.R.4962"[79] and "Protecting
Cyberspace as a National Asset Act of 2010 S.3480"[80] in 2010 none of these has succeeded.
Executive order 13636 Improving Critical Infrastructure Cybersecurity was signed February 12, 2013.
Homeland Security
The Department of Homeland Security has a dedicated division responsible for the response
system, risk management program and requirements for cybersecurity in the United States called
the National Cyber Security Division.[81][82] The division is home to US-CERT operations and the
National Cyber Alert System.[82] The National Cybersecurity and Communications Integration Center
brings together government organizations responsible for protecting computer networks and networked
The third priority of the Federal Bureau of Investigation (FBI) is to: "Protect the United States against
cyber-based attacks and high-technology crimes",[84] and they, along with the National White Collar
Crime Center (NW3C), and the Bureau of Justice Assistance (BJA) are part of the multi-agency task
force, The Internet Crime Complaint Center, also known as IC3.[85]
In addition to its own specific duties, the FBI participates alongside non-profit organizations such
as InfraGard.[86][87]
Department of Justice
In the criminal division of the United States Department of Justice operates a section called
the Computer Crime and Intellectual Property Section. The CCIPS is in charge of
investigating computer crime and intellectual property crime and is specialized in the search and
seizure of digital evidence in computers and networks.[88]
The United States Cyber Command, also known as USCYBERCOM, is tasked with the defense of
specified Department of Defense information networks and "ensure US/Allied freedom of action in
cyberspace and deny the same to our adversaries."[89] It has no role in the protection of civilian
The U.S. Federal Communications Commission's role in cybersecurity is to strengthen the protection
of critical communications infrastructure, to assist in maintaining the reliability of networks during
disasters, to aid in swift recovery after, and to ensure that first responders have access to effective
communications services.[92]
Computer Emergency Readiness Team
Computer Emergency Response Team is a name given to expert groups that handle computer security
incidents. In the US, two distinct organization exist, although they do work closely together.
US-CERT: part of the National Cyber Security Division of the United States Department of
Homeland Security.[93]
CERT/CC: created by the Defense Advanced Research Projects Agency (DARPA) and run by
the Software Engineering Institute (SEI).
International actions
Many different teams and organizations exist, including:
The Forum of Incident Response and Security Teams (FIRST) is the global association of
CSIRTs.[94] The US-CERT, AT&T, Apple, Cisco, McAfee, Microsoft are all members of this international
The Council of Europe helps protect societies worldwide from the threat of cybercrime through
the Convention on Cybercrime.[96]
The purpose of the Messaging Anti-Abuse Working Group (MAAWG) is to bring the messaging
industry together to work collaboratively and to successfully address the various forms of messaging
abuse, such as spam, viruses, denial-of-service attacks and other messaging exploitations.[97] France
Telecom, Facebook, AT&T, Apple, Cisco, Sprint are some of the members of the MAAWG.[98]
ENISA : The European Network and Information Security Agency (ENISA) is an agency of the
European Union with the objective to improve network and information security in the European
CSIRTs in Europe collaborate in the TERENA task force TF-CSIRT. TERENA's Trusted Introducer
service provides an accreditation and certification scheme for CSIRTs in Europe. A full list of known
CSIRTs in Europe is available from the Trusted Introducer website.
National teams
Here are the main computer emergency response teams around the world. Most countries have their
own team to protect network security.
On October 3, 2010, Public Safety Canada unveiled Canada’s Cyber Security Strategy, following a
Speech from the Throne commitment to boost the security of Canadian cyberspace.[99][100] The aim of the
strategy is to strengthen Canada’s "cyber systems and critical infrastructure sectors, support economic
growth and protect Canadians as they connect to each other and to the world."[101] Three main pillars
define the strategy: securing government systems, partnering to secure vital cyber systems outside the
federal government, and helping Canadians to be secure online.[101] The strategy involves multiple
departments and agencies across the Government of Canada.[102] The Cyber Incident Management
Framework for Canada outlines these responsibilities, and provides a plan for coordinated response
between government and other partners in the event of a cyber incident.[103] The Action Plan 20102015
for Canada's Cyber Security Strategy outlines the ongoing implementation of the strategy.[104]
Public Safety Canada’s Canadian Cyber Incident Response Centre (CCIRC) is responsible for mitigating
and responding to threats to Canada’s critical infrastructure and cyber systems. The CCIRC provides
support to mitigate cyber threats, technical support to respond and recover from targeted cyber attacks,
and provides online tools for members of Canada’s critical infrastructure sectors.[105] The CCIRC posts
regular cyber security bulletins on the Public Safety Canada website.[106] The CCIRC also operates an
online reporting tool where individuals and organizations can report a cyber incident.[107] Canada's Cyber
Security Strategy is part of a larger, integrated approach to critical infrastructure protection, and functions
as a counterpart document to the National Strategy and Action Plan for Critical Infrastructure.[102]
On September 27, 2010, Public Safety Canada partnered with STOP.THINK.CONNECT, a coalition of
non-profit, private sector, and government organizations dedicated to informing the general public on
how to protect themselves online.[108] On February 4, 2014, the Government of Canada launched the
Cyber Security Cooperation Program.[109] The program is a $1.5 million five-year initiative aimed at
improving Canada’s cyber systems through grants and contributions to projects in support of this
objective.[110] Public Safety Canada aims to begin an evaluation of Canada's Cyber Security Strategy in
early 2015.[102] Public Safety Canada administers and routinely updates the GetCyberSafe portal for
Canadian citizens, and carries out Cyber Security Awareness Month during October.[111]
China's network security and information technology leadership team was established February 27,
2014. The leadership team is tasked with national security and long-term development and co-ordination
of major issues related to network security and information technology. Economic, political, cultural,
social and military fields as related to network security and information technology strategy, planning and
major macroeconomic policy are being researched. The promotion of national network security and
information technology law are constantly under study for enhanced national security capabilities.
Berlin starts National Cyber Defense Initiative: On June 16, 2011, the German Minister for Home Affairs,
officially opened the new German NCAZ (National Center for Cyber Defense) Nationales Cyber-
Abwehrzentrum located in Bonn. The NCAZ closely cooperates with BSI (Federal Office for Information
Security) Bundesamt für Sicherheit in der Informationstechnik, BKA (Federal Police
Organization) Bundeskriminalamt (Deutschland), BND (Federal Intelligence
Service) Bundesnachrichtendienst, MAD (Military Intelligence Service) Amt für den Militärischen
Abschirmdienst and other national organizations in Germany taking care of national security aspects.
According to the Minister the primary task of the new organization founded on February 23, 2011, is to
detect and prevent attacks against the national infrastructure and mentioned incidents like Stuxnet.
Some provisions for cybersecurity have been incorporated into rules framed under the Information
Technology Act 2000.
The National Cyber Security Policy 2013 is a policy framework by Department of Electronics and
Information Technology (DeitY) which aims to protect the public and private infrastructure from cyber
attacks, and safeguard "information, such as personal information (of web users), financial and banking
information and sovereign data".
The Indian Companies Act 2013 has also introduced cyber law and cyber security obligations on the
part of Indian directors.
Cyber-crime has risen rapidly in Pakistan. There are about 30 million internet users with 15 million mobile
subscribers in Pakistan. According to Cyber Crime Unit (CCU), a branch of Federal Investigation Agency,
only 62 cases were reported to the unit in 2007, 287 cases in 2008, ratio dropped in 2009 but in 2010,
more than 312 cases were registered. But unreported incidents of cyber-crime are huge in numbers.[112]
The first ever pertinent law, i.e. “Pakistan’s Cyber Crime Bill 2007”, which focuses on electronic crimes,
i.e. cyber terrorism, criminal access, electronic system fraud, electronic forgery, misuse of encryption etc.
has been there.[113]
National Response Centre for Cyber Crime (NR3C) - FIA is a law enforcement agency dedicated to fight
cyber crime. Inception of this Hi-Tech crime fighting unit transpired in 2007 to identify and curb the
phenomenon of technological abuse in society.[114] However along with that certain private firms are also
working in cohesion with Govt to work towards cyber security and curb cyber attacks[115]
South Korea
Following cyberattacks in the first half of 2013, when government, news-media, television station, and
bank websites were compromised, the national government committed to the training of 5,000 new
cybersecurity experts by 2017. The South Korean government blamed its northern counterpart for these
attacks, as well as incidents that occurred in 2009, 2011,[116] and 2012, but Pyongyang denies the
Other countries
CERT Brazil, member of FIRST (Forum for Incident Response and Security Teams)
CARNet CERT, Croatia, member of FIRST
AE CERT, United Arab Emirates
SingCERT, Singapore
CERT-LEXSI, France, Canada, Singapore
Modern warfare
Cybersecurity is becoming increasingly important as more information and technology is being made
available on cyberspace. There is growing concern among governments that cyberspace will become the
next theatre of warfare. As Mark Clayton from the Christian Science Monitor described in an article titled
"The New Cyber Arms Race":
In the future, wars will not just be fought by soldiers with guns or with planes that drop bombs. They will
also be fought with the click of a mouse a half a world away that unleashes carefully weaponized
computer programs that disrupt or destroy critical industries like utilities, transportation, communications,
and energy. Such attacks could also disable military networks that control the movement of troops, the
path of jet fighters, the command and control of warships.[118]
This has led to new terms such as cyberwarfare and cyberterrorism. More and more critical
infrastructure is being controlled via computer programs that, while increasing efficiency, exposes new
vulnerabilities. The test will be to see if governments and corporations that control critical systems such
as energy, communications and other information will be able to prevent attacks before they occur. As
Jay Cross, the chief scientist of the Internet Time Group, remarked, "Connectedness begets
The cyber security job market
Cyber Security is a fast-growing[119] field of IT concerned with reducing organizations' risk of hack or data
breach. Commercial, government and non-governmental organizations all employ cybersecurity
professionals. However, the use of the term "cybersecurity" is more prevalent in government job
Typical cybersecurity job titles and descriptions include:[121]
Security Analyst
Analyzes and assesses vulnerabilities in the infrastructure (software, hardware, networks), investigates
available tools and countermeasures to remedy the detected vulnerabilities, and recommends solutions
and best practices. Analyzes and assesses damage to the data/infrastructure as a result of security
incidents, examines available recovery tools and processes, and recommends solutions. Tests for
compliance with security policies and procedures. May assist in the creation, implementation, and/or
management of security solutions.
Security Engineer
Performs security monitoring, security and data/logs analysis, and forensic analysis, to detect security
incidents, and mounts incident response. Investigates and utilizes new technologies and processes to
enhance security capabilities and implement improvements. May also review code or perform other
security engineering methodologies.
Security Architect
Designs a security system or major components of a security system, and may head a security design
team building a new security system.
Security Administrator
Installs and manages organization-wide security systems. May also take on some of the tasks of a
security analyst in smaller organizations.
Chief Information Security Officer (CISO)
A high-level management position responsible for the entire information security division/staff. The
position may include hands-on technical work.
Chief Security Officer (CSO)
A high-level management position responsible for the entire security division/staff. A newer position now
deemed needed as security risks grow.
Security Consultant/Specialist/Intelligence
Broad titles that encompass any one or all of the other roles/titles, tasked with protecting computers,
networks, software, data, and/or information systems against viruses, worms, spyware, malware,
intrusion detection, unauthorized access, denial-of-service attacks, and an ever increasing list of attacks
by hackers acting as individuals or as part of organized crime or foreign governments.
Student programs are also available to people interested in beginning a career in cybersecurity.[122][123]
Meanwhile, a flexible and effective option for information security professionals of all experience levels
to keep studying is online security training, including webcasts.[124][125][126]
The following terms used with regards to engineering secure systems are explained below.
Access authorization restricts access to a computer to group of users through the use of
authentication systems. These systems can protect either the whole computer such as through an
interactive login screen or individual services, such as an FTP server. There are many methods for
identifying and authenticating users, such as passwords, identification cards, and, more recently, smart
cards and biometric systems.
Anti-virus software consists of computer programs that attempt to identify, thwart and eliminate
computer viruses and other malicious software (malware).
Applications with known security flaws should not be run. Either leave it turned off until it can be
patched or otherwise fixed, or delete it and replace it with some other application. Publicly known flaws
are the main entry used by worms to automatically break into a system and then spread to other
systems connected to it. The security website Secunia provides a search tool for unpatched known flaws
in popular products.
Authentication techniques can be used to ensure that communication end-points are who they
say they are.
Automated theorem proving and other verification tools can enable critical algorithms and code
used in secure systems to be mathematically proven to meet their specifications.
Backups are a way of securing information; they are another copy of all the important computer
files kept in another location. These files are kept on hard disks, CD-Rs, CD-RWs, tapes and more
recently on the cloud. Suggested locations for backups are a fireproof, waterproof, and heat proof safe,
or in a separate, offsite location than that in which the original files are contained. Some individuals and
companies also keep their backups in safe deposit boxes inside bank vaults. There is also a fourth
option, which involves using one of the file hosting services that backs up files over the Internet for
both business and individuals, known as the cloud.
Backups are also important for reasons other than security. Natural disasters, such as earthquakes,
hurricanes, or tornadoes, may strike the building where the computer is located. The building can be on
fire, or an explosion may occur. There needs to be a recent backup at an alternate secure location, in
case of such kind of disaster. Further, it is recommended that the alternate location be placed where the
same disaster would not affect both locations. Examples of alternate disaster recovery sites being
compromised by the same disaster that affected the primary site include having had a primary site in
World Trade Center I and the recovery site in 7 World Trade Center, both of which were destroyed in
the 9/11 attack, and having one's primary site and recovery site in the same coastal region, which leads
to both being vulnerable to hurricane damage (for example, primary site in New Orleans and recovery
site in Jefferson Parish, both of which were hit by Hurricane Katrina in 2005). The backup media should
be moved between the geographic sites in a secure manner, in order to prevent them from being stolen.
Capability and access control list techniques can be used to ensure privilege separation and
mandatory access control. This section discusses their use.
Chain of trust techniques can be used to attempt to ensure that all software loaded has been
certified as authentic by the system's designers.
Confidentiality is the nondisclosure of information except to another authorized person.[127]
Cryptographic techniques can be used to defend data in transit between systems, reducing the
probability that data exchanged between systems can be intercepted or modified.
Cyberwarfare is an Internet-based conflict that involves politically motivated attacks on
information and information systems. Such attacks can, for example, disable official websites and
networks, disrupt or disable essential services, steal or alter classified data and cripple financial systems.
Data integrity is the accuracy and consistency of stored data, indicated by an absence of any
alteration in data between two updates of a data record.[128]
Cryptographic techniques involve transforming information, scrambling it so it becomes unreadable
during transmission. The intended recipient can unscramble the message; ideally, eavesdroppers
Encryption is used to protect the message from the eyes of others. Cryptographically secure
ciphers are designed to make any practical attempt of breaking infeasible. Symmetric-key ciphers are
suitable for bulk encryption using shared keys, and public-key encryption using digital certificates can
provide a practical solution for the problem of securely communicating when no key is shared in
Endpoint security software helps networks to prevent exfiltration (data theft) and virus infection at
network entry points made vulnerable by the prevalence of potentially infected portable computing
devices, such as laptops and mobile devices, and external storage devices, such as USB drives.[129]
Firewalls are an important method for control and security on the Internet and other networks. A
network firewall can be a communications processor, typically a router, or a dedicated server, along with
firewall software. A firewall serves as a gatekeeper system that protects a company's intranets and other
computer networks from intrusion by providing a filter and safe transfer point for access to and from the
Internet and other networks. It screens all network traffic for proper passwords or other security codes
and only allows authorized transmission in and out of the network. Firewalls can deter, but not
completely prevent, unauthorized access (hacking) into computer networks; they can also provide some
protection from online intrusion.
Honey pots are computers that are either intentionally or unintentionally left vulnerable to attack
by crackers. They can be used to catch crackers or fix vulnerabilities.
Intrusion-detection systems can scan a network for people that are on the network but who
should not be there or are doing things that they should not be doing, for example trying a lot of
passwords to gain access to the network.
A microkernel is the near-minimum amount of software that can provide the mechaniSMS to
implement an operating system. It is used solely to provide very low-level, very precisely defined
machine code upon which an operating system can be developed. A simple example is the early '90s
GEMSOS (Gemini Computers), which provided extremely low-level machine code, such as "segment"
management, atop which an operating system could be built. The theory (in the case of "segments") was
thatrather than have the operating system itself worry about mandatory access separation by means of
military-style labelingit is safer if a low-level, independently scrutinized module can be charged solely
with the management of individually labeled segments, be they memory "segments" or file system
"segments" or executable text "segments." If software below the visibility of the operating system is (as in
this case) charged with labeling, there is no theoretically viable means for a clever hacker to subvert the
labeling scheme, since the operating system per se does not provide mechaniSMS for interfering with
labeling: the operating system is, essentially, a client (an "application," arguably) atop the microkernel
and, as such, subject to its restrictions.
Pinging The ping application can be used by potential crackers to find if an IP address is
reachable. If a cracker finds a computer, they can try a port scan to detect and attack services on that
Social engineering awareness keeps employees aware of the dangers of social engineering
and/or having a policy in place to prevent social engineering can reduce successful breaches of the
network and servers.
Mobile security
Mobile security or mobile phone security has become increasingly important in mobile computing.
Of particular concern is the security of personal and business information now stored on smartphones.
More and more users and businesses employ smartphones as communication tools, but also as a
means of planning and organizing their work and private life. Within companies, these technologies are
causing profound changes in the organization of information systems and therefore they have become
the source of new risks. Indeed, smartphones collect and compile an increasing amount of sensitive
information to which access must be controlled to protect the privacy of the user and the intellectual
property of the company.
All smartphones, as computers, are preferred targets of attacks. These attacks exploit weaknesses
related to smartphones that can come from means of communication like Short Message Service
(SMS, aka text messaging), Multimedia Messaging Service (MMS), Wi-Fi networks, Bluetooth and
GSM, the de facto global standard for mobile communications. There are also attacks that exploit
software vulnerabilities from both the web browser and operating system. Finally, there are forms of
malicious software that rely on the weak knowledge of average users.
Different security counter-measures are being developed and applied to smartphones, from security in
different layers of software to the dissemination of information to end users. There are good practices to
be observed at all levels, from design to use, through the development of operating systems, software
layers, and downloadable apps.
Challenges of mobile security
A smartphone user is exposed to various threats when they use their phone. In just the last two quarters
of 2012, the number of unique mobile threats grew by 261%, according to ABI Research.[1] These
threats can disrupt the operation of the smartphone, and transmit or modify user data. For these reasons,
the applications deployed there must guarantee privacy and integrity of the information they handle. In
addition, since some apps could themselves be malware, their functionality and activities should be
limited (for example, restricting the apps from accessing location information via GPS, blocking access to
the user's address book, preventing the transmission of data on the network, sending SMS messages
that are billed to the user, etc.).
There are three prime targets for attackers:[2]
Data: smartphones are devices for data management, therefore they may contain sensitive data
like credit card numbers, authentication information, private information, activity logs (calendar, call logs);
Identity: smartphones are highly customizable, so the device or its contents are associated with
a specific person. For example, every mobile device can transmit information related to the owner of the
mobile phone contract, and an attacker may want to steal the identity of the owner of a smartphone to
commit other offenses;
Availability: by attacking a smartphone one can limit access to it and deprive the owner of the
The source of these attacks are the same actors found in the non-mobile computing space:[2]
Professionals, whether commercial or military, who focus on the three targets mentioned above.
They steal sensitive data from the general public, as well as undertake industrial espionage. They will
also use the identity of those attacked to achieve other attacks;
Thieves who want to gain income through data or identities they have stolen. The thieves will
attack many people to increase their potential income;
Black hat hackers who specifically attack availability.[3] Their goal is to develop viruses, and
cause damage to the device.[4] In some cases, hackers have an interest in stealing data on devices.
Grey hat hackers who reveal vulnerabilities.[5] Their goal is to expose vulnerabilities of the
device.[6] Grey hat hackers do not intend on damaging the device or stealing data.[7]
When a smartphone is infected by an attacker, the attacker can attempt several things:
The attacker can manipulate the smartphone as a zombie machine, that is to say, a machine
with which the attacker can communicate and send commands which will be used to send unsolicited
messages (spam) via SMS or email;[8]
The attacker can easily force the smartphone to make phone calls. For example, one can use
the API (library that contains the basic functions not present in the smartphone) PhoneMakeCall
by Microsoft, which collects telephone numbers from any source such as yellow pages, and then call
them.[8] But the attacker can also use this method to call paid services, resulting in a charge to the owner
of the smartphone. It is also very dangerous because the smartphone could call emergency services and
thus disrupt those services;[8]
A compromised smartphone can record conversations between the user and others and send
them to a third party.[8] This can cause user privacy and industrial security problems;
An attacker can also steal a user's identity, usurp their identity (with a copy of the user's sim card
or even the telephone itself), and thus impersonate the owner. This raises security concerns in countries
where smartphones can be used to place orders, view bank accounts or are used as an identity card;[8]
The attacker can reduce the utility of the smartphone, by discharging the battery.[9] For example,
they can launch an application that will run continuously on the smartphone processor, requiring a lot of
energy and draining the battery. One factor that distinguishes mobile computing from traditional desktop
PCs is their limited performance. Frank Stajano and Ross Anderson first described this form of attack,
calling it an attack of "battery exhaustion" or "sleep deprivation torture";[10]
The attacker can prevent the operation and/or starting of the smartphone by making it
unusable.[11] This attack can either delete the boot scripts, resulting in a phone without a functioning OS,
or modify certain files to make it unusable (e.g. a script that launches at startup that forces the
smartphone to restart) or even embed a startup application that would empty the battery;[10]
The attacker can remove the personal (photos, music, videos, etc.) or professional data
(contacts, calendars, notes) of the user.[11]
Attacks based on communication
Attack based on SMS and MMS
Some attacks derive from flaws in the management of SMS and MMS.
Some mobile phone models have problems in managing binary SMS messages. It is possible, by
sending an ill-formed block, to cause the phone to restart, leading to denial of service attacks. If a user
with a Siemens S55 received a text message containing a Chinese character, it would lead to a denial of
service.[12] In another case, while the standard requires that the maximum size of a Nokia Mail address is
32 characters, some Nokia phones did not verify this standard, so if a user enters an email address over
32 characters, that leads to complete dysfunction of the e-mail handler and puts it out of commission.
This attack is called "curse of silence". A study on the safety of the SMS infrastructure revealed that SMS
messages sent from the Internet can be used to perform a distributed denial of service (DDoS) attack
against the mobile telecommunications infrastructure of a big city. The attack exploits the delays in the
delivery of messages to overload the network.
Another potential attack could begin with a phone that sends an MMS to other phones, with an
attachment. This attachment is infected with a virus. Upon receipt of the MMS, the user can choose to
open the attachment. If it is opened, the phone is infected, and the virus sends an MMS with an infected
attachment to all the contacts in the address book. There is a real world example of this attack: the virus
Commwarrior [11] uses the address book and sends MMS messages including an infected file to
recipients. A user installs the software, as received via MMS message. Then, the virus began to send
messages to recipients taken from the address book.
Attacks based on communication networks
Attacks based on the GSM networks
The attacker may try to break the encryption of the mobile network. The GSM network encryption
algorithms belong to the family of algorithms called A5. Due to the policy of security through obscurity
it has not been possible to openly test the robustness of these algorithms. There were originally two
variants of the algorithm: A5/1 and A5/2 (stream ciphers), where the former was designed to be relatively
strong, and the latter was designed to be weak on purpose to allow easy cryptanalysis and
eavesdropping. ETSI forced some countries (typically outside Europe) to use A5/2. Since the encryption
algorithm was made public, it was proved it was possible to break the encryption: A5/2 could be broken
on the fly, and A5/1 in about 6 hours .[13] In July 2007, the 3GPP approved a change request to prohibit
the implementation of A5/2 in any new mobile phones, which means that is has been decommissioned
and is no longer implemented in mobile phones. Stronger public algorithms have been added to the GSM
standard, the A5/3 and A5/4 (Block ciphers), otherwise known as KASUMI or UEA1[14] published by
the ETSI. If the network does not support A5/1, or any other A5 algorithm implemented by the phone,
then the base station can specify A5/0 which is the null-algorithm, whereby the radio traffic is sent
unencrypted. Even in case mobile phones are able to use 3G or 4G which have much stronger
encryption than 2G GSM, the base station can downgrade the radio communication to 2G GSM and
specify A5/0 (no encryption) .[15] This is the basis for eavesdropping attacks on mobile radio networks
using a fake base station commonly called an IMSI catcher.
In addition, tracing of mobile terminals is difficult since each time the mobile terminal is accessing or
being accessed by the network, a new temporary identity (TMSI) is allocated to the mobile terminal. The
TSMI is used as identity of the mobile terminal the next time it accesses the network. The TMSI is sent to
the mobile terminal in encrypted messages.
Once the encryption algorithm of GSM is broken, the attacker can intercept all unencrypted
communications made by the victim's smartphone.
Attacks based on Wi-Fi
Access Point spoofing
An attacker can try to eavesdrop on Wi-Fi communications to derive information (e.g. username,
password). This type of attack is not unique to smartphones, but they are very vulnerable to these
attacks because very often the Wi-Fi is the only means of communication they have to access the
internet. The security of wireless networks (WLAN) is thus an important subject. Initially wireless
networks were secured by WEP keys. The weakness of WEP is a short encryption key which is the same
for all connected clients. In addition, several reductions in the search space of the keys have been found
by researchers. Now, most wireless networks are protected by the WPA security protocol. WPA is based
on the "Temporal Key Integrity Protocol (TKIP)" which was designed to allow migration from WEP to
WPA on the equipment already deployed. The major improvements in security are the dynamic
encryption keys. For small networks, the WPA is a "pre-shared key" which is based on a shared key.
Encryption can be vulnerable if the length of the shared key is short. With limited opportunities for input
(i.e. only the numeric keypad) mobile phone users might define short encryption keys that contain only
numbers. This increases the likelihood that an attacker succeeds with a brute-force attack. The
successor to WPA, called WPA2, is supposed to be safe enough to withstand a brute force attack.
As with GSM, if the attacker succeeds in breaking the identification key, it will be possible to attack not
only the phone but also the entire network it is connected to.
Many smartphones for wireless LANs remember they are already connected, and this mechanism
prevents the user from having to re-identify with each connection. However, an attacker could create a
WIFI access point twin with the same parameters and characteristics as the real network. Using the fact
that some smartphones remember the networks, they could confuse the two networks and connect to the
network of the attacker who can intercept data if it does not transmit its data in encrypted form.[16][17] [18]
Lasco is a worm that initially infects a remote device using the SIS file format.[19] SIS file format
(Software Installation Script) is a script file that can be executed by the system without user interaction.
The smartphone thus believes the file to come from a trusted source and downloads it, infecting the
Principle of Bluetooth-based attacks
Security issues related to Bluetooth on mobile devices have been studied and have shown numerous
problems on different phones. One easy to exploit vulnerability: unregistered services do not require
authentication, and vulnerable applications have a virtual serial port used to control the phone. An
attacker only needed to connect to the port to take full control of the device.[20] Another example: a phone
must be within reach and Bluetooth in discovery mode. The attacker sends a file via Bluetooth. If the
recipient accepts, a virus is transmitted. For example: Cabir is a worm that spreads via Bluetooth
connection.[11] The worm searches for nearby phones with Bluetooth in discoverable mode and sends
itself to the target device. The user must accept the incoming file and install the program. After installing,
the worm infects the machine.
Attacks based on vulnerabilities in software applications
Other attacks are based on flaws in the OS or applications on the phone.
The mobile web browser is an emerging attack vector for mobile devices. Just as common Web
browsers, mobile web browsers are extended from pure web navigation with widgets and plug-ins, or
are completely native mobile browsers.
Jailbreaking the iPhone with firmware 1.1.1 was based entirely on vulnerabilities on the web
browser.[21] As a result, the exploitation of the vulnerability described here underlines the importance of
the Web browser as an attack vector for mobile devices. In this case, there was a vulnerability based on
a stack-based buffer overflow in a library used by the web browser (Libtiff).
A vulnerability in the web browser for Android was discovered in October 2008. As the iPhone
vulnerability above, it was due to an obsolete and vulnerable library. A significant difference with the
iPhone vulnerability was Android's sandboxing architecture which limited the effects of this vulnerability
to the Web browser process.
Smartphones are also victims of classic piracy related to the web: phishing, malicious websites, etc. The
big difference is that smartphones do not yet have strong antivirus software available.
Operating system
Sometimes it is possible to overcome the security safeguards by modifying the operating system itself.
As real-world examples, this section covers the manipulation of firmware and malicious signature
certificates. These attacks are difficult.
In 2004, vulnerabilities in virtual machines running on certain devices were revealed. It was possible to
bypass the bytecode verifier and access the native underlying operating system. The results of this
research were not published in detail. The firmware security of Nokia's Symbian Platform Security
Architecture (PSA) is based on a central configuration file called SWIPolicy. In 2008 it was possible to
manipulate the Nokia firmware before it is installed, and in fact in some downloadable versions of it, this
file was human readable, so it was possible to modify and change the image of the firmware.[22] This
vulnerability has been solved by an update from Nokia.
In theory smartphones have an advantage over hard drives since the OS files are in ROM, and cannot
be changed by malware. However, in some systems it was possible to circumvent this: in the Symbian
OS it was possible to overwrite a file with a file of the same name.[22] On the Windows OS, it was
possible to change a pointer from a general configuration file to an editable file.
When an application is installed, the signing of this application is verified by a series of certificates.
One can create a valid signature without using a valid certificate and add it to the list.[23] In the Symbian
OS all certificates are in the directory: c:\resource\swicertstore\dat. With firmware changes explained
above it is very easy to insert a seemingly valid but malicious certificate.
Attacks based on hardware vulnerabilities
Electromagnetic Waveforms
In 2015, researchers at the French government agency ANSSI demonstrated the capability to trigger the
voice interface of certain smartphones remotely by using "specific electromagnetic waveforms".[24] The
exploit took advantage of antenna-properties of headphone wires while plugged into the audio-output
jacks of the vulnerable smartphones and effectively spoofed audio input to inject commands via the
audio interface.[24]
Juice Jacking
Juice Jacking is a method of physical or a hardware vulnerability specific to mobile platforms. Utilizing
the dual purpose of the USB charge port, many devices have been susceptible to having data ex-filtrated
from, or malware installed on to a mobile device by utilizing malicious charging kiosks set up in public
places, or hidden in normal charge adapters.
Password cracking
In 2010, researcher from the University of Pennsylvania investigated the possibility of cracking a
device's password through a smudge attack (literally imaging the finger smudges on the screen to
discern the user's password).[25] The researchers were able to discern the device password up to 68% of
the time under certain conditions.[25]
Malicious software (malware)
As smartphones are a permanent point of access to the internet (mostly on), they can be compromised
as easily as computers with malware.[26] A malware is a computer program that aims to harm the system
in which it resides. Trojans, worms and viruses are all considered malware. A Trojan is a program that
is on the smartphone and allows external users to connect discreetly. A worm is a program that
reproduces on multiple computers across a network. A virus is malicious software designed to spread to
other computers by inserting itself into legitimate programs and running programs in parallel. However, it
must be said that the malware are far less numerous and important to smartphones as they are to
Nonetheless, recent studies show that the evolution of malware in smartphones have rocketed in the last
few years posing a threat to analysis and detection.[28]
The three phases of malware attacks
Typically an attack on a smartphone made by malware takes place in 3 phases: the infection of a host,
the accomplishment of its goal, and the spread of the malware to other systems. Malware often use the
resources offered by the infected smartphones. It will use the output devices such as Bluetooth or
infrared, but it may also use the address book or email address of the person to infect the user's
acquaintances. The malware exploits the trust that is given to data sent by an acquaintance.
Infection is the means used by the malware to get into the smartphone, it can either use one of the faults
previously presented or may use the gullibility of the user. Infections are classified into four classes
according to their degree of user interaction:[29]
Explicit permission
The most benign interaction is to ask the user if it is allowed to infect the machine, clearly indicating its
potential malicious behavior. This is typical behavior of a proof of concept malware.
Implied permission
This infection is because the user has a habit of installing software. Most Trojans try to seduce the user
into installing attractive applications (games, useful applications etc.) that actually contain malware.
Common interaction
This infection is related to a common behavior, such as opening an MMS or email.
No interaction
The last class of infection is the most dangerous. Indeed, a worm that could infect a smartphone and
could infect other smartphones without any interaction would be catastrophic.
Accomplishment of its goal
Once the malware has infected a phone it will also seek to accomplish its goal, which is usually one of
the following: monetary damage, damage data and/or device, and concealed damage:[30]
Monetary damages
The attacker can steal user data and either sell them to the same user, or sell to a third party.
Malware can partially damage the device, or delete or modify data on the device.
Concealed damage
The two aforementioned types of damage are detectable, but the malware can also leave a backdoor for
future attacks or even conduct wiretaps.
Spread to other systems
Once the malware has infected a smartphone, it always aims to spread one way or another:[31]
It can spread through proximate devices using Wi-Fi, Bluetooth and infrared;
It can also spread using remote networks such as telephone calls or SMS or emails.
Examples of malware
Here are various malware that exist in the world of smartphones with a short description of each.
Viruses and Trojans
Cabir (also known as Caribe, SybmOS/Cabir, Symbian/Cabir and EPOC.cabir) is the name of
a computer worm developed in 2004 that is designed to infect mobile phones running Symbian OS. It is
believed to be the first computer worm that can infect mobile phones
Commwarrior, found March 7, 2005, is the first worm that can infect many machines from
MMS.[11] It is sent in the form of an archive file COMMWARRIOR.ZIP that contains a file
COMMWARRIOR.SIS. When this file is executed, Commwarrior attempts to connect to nearby devices
by Bluetooth or infrared under a random name. It then attempts to send MMS message to the contacts
in the smartphone with different header messages for each person, who receive the MMS and often
open them without further verification.
Phage is the first Palm OS virus that was discovered.[11] It transfers to the Palm from a PC via
synchronization. It infects all applications that are in the smartphone and it embeds its own code to
function without the user and the system detecting it. All that the system will detect is that its usual
applications are functioning.
RedBrowser is a Trojan which is based on java.[11] The Trojan masquerades as a program
called "RedBrowser" which allows the user to visit WAP sites without a WAP connection. During
application installation, the user sees a request on their phone that the application needs permission to
send messages. Therefore, if the user accepts, RedBrowser can send SMS to paid call centers. This
program uses the smartphone's connection to social networks (Facebook, Twitter, etc.) to get the
contact information for the user's acquaintances (provided the required permissions have been given)
and will send them messages.
WinCE.PmCryptic.A is a malicious software on Windows Mobile which aims to earn money for
its authors. It uses the infestation of memory cards that are inserted in the smartphone to spread more
CardTrap is a virus that is available on different types of smartphone, which aims to deactivate
the system and third party applications. It works by replacing the files used to start the smartphone and
applications to prevent them from executing.[33] There are different variants of this virus such as
Cardtrap.A for SymbOS devices. It also infects the memory card with malware capable of infecting
Ghost Push is a malicious software on Android OS which automatically root the android device
and installs malicious applications directly to system partition then unroots the device to prevent users
from removing the threat by master reset (The threat can be removed only by reflashing). It cripples the
system resources, executes quickly, and harder to detect.
Mobile ransomware is a type of malware that locks users out of their mobile devices in a pay-to-unlock-
your-device ploy, it has grown by leaps and bounds as a threat category since 2014.[34] Specific to
mobile computing platforms, users are often less security-conscious, particularly as it pertains to
scrutinizing applications and web links trusting the native protection capability of the mobile device
operating system. Mobile ransomware poses a significant threat to businesses reliant on instant access
and availability of their proprietary information and contacts. The likelihood of a traveling businessman
paying a ransom to unlock their device is significantly higher since they are at a disadvantage given
inconveniences such as timeliness and less likely direct access to IT staff.
Flexispy is an application that can be considered as a Trojan, based on Symbian. The program
sends all information received and sent from the smartphone to a Flexispy server. It was originally
created to protect children and spy on adulterous spouses.[11]
Number of malware
Below is a diagram which loads the different behaviors of smartphone malware in terms of their effects
on smartphones:[27]
Effects of Malware
We can see from the graph that at least 66% malwares are the majority that exhibits no negative
behavior, except their ability to spread.[27]
Portability of malware across platforms
There is a multitude of malware. This is partly due to the variety of operating systems on smartphones.
However, attackers can also choose to make their malware target multiple platforms, and malware can
be found which attacks an OS but is able to spread to different systems.
To begin with, malware can use runtime environments like Java virtual machine or the .NET
Framework. They can also use other libraries present in many operating systems.[35] Other malware
carry several executable files in order to run in multiple environments and they utilize these during the
propagation process. In practice, this type of malware requires a connection between the two operating
systems to use as an attack vector. Memory cards can be used for this purpose, or synchronization
software can be used to propagate the virus.
The security mechaniSMS in place to counter the threats described above are presented in this section.
They are divided into different categories, as all do not act at the same level, and they range from the
management of security by the operating system to the behavioral education of the user. The threats
prevented by the various measures are not the same depending on the case. Considering the two cases
mentioned above, in the first case one would protect the system from corruption by an application, and in
the second case the installation of a suspicious software would be prevented.
Security in operating systems
The first layer of security within a smartphone is at the level of the operating system (OS). Beyond the
usual roles of an operating system (e.g. resource management, scheduling processes) on a smartphone,
it must also establish the protocols for introducing external applications and data without introducing risk.
A central idea found in the mobile operating systems is the idea of a sandbox. Since smartphones are
currently being designed to accommodate many applications, they must put in place mechaniSMS to
ensure these facilities are safe for themselves, for other applications and data on the system, and the
user. If a malicious program manages to reach a device, it is necessary that the vulnerable area
presented by the system be as small as possible. Sandboxing extends this idea to compartmentalize
different processes, preventing them from interacting and damaging each other. Based on the history of
operating systems, sandboxing has different implementations. For example, where iOS will focus on
limiting access to its public API for applications from the App Store by default, Managed Open In allows
you to restrict which apps can access which types of data. Android bases its sandboxing on its legacy of
Linux and TrustedBSD.
Rootkit Detectors
The intrusion of a rootkit in the system is a great danger in the same way as on a computer. It is
important to prevent such intrusions, and to be able to detect them as often as possible. Indeed, there is
concern that with this type of malicious program, the result could be a partial or complete bypass of the
device security, and the acquisition of administrator rights by the attacker. If this happens, then nothing
prevents the attacker from studying or disabling the safety features that were circumvented, deploying
the applications they want, or disseminating a method of intrusion by a rootkit to a wider audience.[36][37]
We can cite, as a defense mechanism, the Chain of trust in iOS. This mechanism relies on the
signature of the different applications required to start the operating system, and a certificate signed by
Apple. In the event that the signature checks are inconclusive, the device detects this and stops the boot-
up.[38] If the Operating System is compromised due to Jailbreaking, root kit detection may not work if it is
disabled by the Jailbreak method or software is loaded after Jailbreak disables Rootkit Detection.
Process isolation
Android uses mechaniSMS of user process isolation inherited from Linux. Each application has a user
associated with it, and a tuple (UID, GID). This approach serves as a sandbox: while applications can be
malicious, they cannot get out of the sandbox reserved for them by their identifiers, and thus cannot
interfere with the proper functioning of the system. For example, since it is impossible for a process to
end the process of another user, an application can thus not stop the execution of another.[36][39][40][41][42]
File permissions
From the legacy of Linux, there are also filesystem permissions mechaniSMS. They help with
sandboxing: a process cannot edit any files it wants. It is therefore not possible to freely corrupt files
necessary for the operation of another application or system. Furthermore, in Android there is the
method of locking memory permissions. It is not possible to change the permissions of files installed on
the SD card from the phone, and consequently it is impossible to install applications.[43][44][45]
Memory Protection
In the same way as on a computer, memory protection prevents privilege escalation. Indeed, if a
process managed to reach the area allocated to other processes, it could write in the memory of a
process with rights superior to their own, with root in the worst case, and perform actions which are
beyond its permissions on the system. It would suffice to insert function calls are authorized by the
privileges of the malicious application.[42]
Development through runtime environments
Software is often developed in high-level languages, which can control what is being done by a running
program. For example, Java Virtual Machines continuously monitor the actions of the execution threads
they manage, monitor and assign resources, and prevent malicious actions. Buffer overflows can be
prevented by these controls.[46][47][42]
Security software
Above the operating system security, there is a layer of security software. This layer is composed of
individual components to strengthen various vulnerabilities: prevent malware, intrusions, the identification
of a user as a human, and user authentication. It contains software components that have learned from
their experience with computer security; however, on smartphones, this software must deal with greater
Antivirus and firewall
An antivirus software can be deployed on a device to verify that it is not infected by a known threat,
usually by signature detection software that detects malicious executable files. A firewall, meanwhile,
can watch over the existing traffic on the network and ensure that a malicious application does not seek
to communicate through it. It may equally verify that an installed application does not seek to establish
suspicious communication, which may prevent an intrusion attempt.[48][49][50][37]
Visual Notifications
In order to make the user aware of any abnormal actions, such as a call they did not initiate, one can link
some functions to a visual notification that is impossible to circumvent. For example, when a call is
triggered, the called number should always be displayed. Thus, if a call is triggered by a malicious
application, the user can see, and take appropriate action.
Turing test
In the same vein as above, it is important to confirm certain actions by a user decision. The Turing test
is used to distinguish between a human and a virtual user, and it often comes as a captcha.
Biometric identification
Another method to use is biometrics.[51] Biometrics is a technique of identifying a person by means of
their morphology(by recognition of the eye or face, for example) or their behavior (their signature or way
of writing for example). One advantage of using biometric security is that users can avoid having to
remember a password or other secret combination to authenticate and prevent malicious users from
accessing their device. In a system with strong biometric security, only the primary user can access the
Resource monitoring in the smartphone
When an application passes the various security barriers, it can take the actions for which it was
designed. When such actions are triggered, the activity of a malicious application can be sometimes
detected if one monitors the various resources used on the phone. Depending on the goals of the
malware, the consequences of infection are not always the same; all malicious applications are not
intended to harm the devices on which they are deployed. The following sections describe different ways
to detect suspicious activity.[52]
Some malware is aimed at exhausting the energy resources of the phone. Monitoring the energy
consumption of the phone can be a way to detect certain malware applications.[36]
Memory usage
Memory usage is inherent in any application. However, if one finds that a substantial proportion of
memory is used by an application, it may be flagged as suspicious.
Network traffic
On a smartphone, many applications are bound to connect via the network, as part of their normal
operation. However, an application using a lot of bandwidth can be strongly suspected of attempting to
communicate a lot of information, and disseminate data to many other devices. This observation only
allows a suspicion, because some legitimate applications can be very resource-intensive in terms of
network communications, the best example being streaming video.
One can monitor the activity of various services of a smartphone. During certain moments, some
services should not be active, and if one is detected, the application should be suspected. For example,
the sending of an SMS when the user is filming video: this communication does not make sense and is
suspicious; malware may attempt to send SMS while its activity is masked.[53]
The various points mentioned above are only indications and do not provide certainty about the
legitimacy of the activity of an application. However, these criteria can help target suspicious
applications, especially if several criteria are combined.
Network surveillance
Network traffic exchanged by phones can be monitored. One can place safeguards in network routing
points in order to detect abnormal behavior. As the mobile's use of network protocols is much more
constrained than that of a computer, expected network data streams can be predicted (e.g. the protocol
for sending an SMS), which permits detection of anomalies in mobile networks.
Spam filters
As is the case with email exchanges, we can detect a spam campaign through means of mobile
communications (SMS, MMS). It is therefore possible to detect and minimize this kind of attempt by
filters deployed on network infrastructure that is relaying these messages.
Encryption of stored or transmitted information
Because it is always possible that data exchanged can be intercepted, communications, or even
information storage, can rely on encryption to prevent a malicious entity from using any data obtained
during communications. However, this poses the problem of key exchange for encryption algorithms,
which requires a secure channel.
Telecom network monitoring
The networks for SMS and MMS exhibit predictable behavior, and there is not as much liberty compared
with what one can do with protocols such as TCP or UDP. This implies that one cannot predict the use
made of the common protocols of the web; one might generate very little traffic by consulting simple
pages, rarely, or generate heavy traffic by using video streaming. On the other hand, messages
exchanged via mobile phone have a framework and a specific model, and the user does not, in a normal
case, have the freedom to intervene in the details of these communications. Therefore, if an abnormality
is found in the flux of network data in the mobile networks, the potential threat can be quickly detected.
Manufacturer surveillance
In the production and distribution chain for mobile devices, it is the responsibility of manufacturers to
ensure that devices are delivered in a basic configuration without vulnerabilities. Most users are not
experts and many of them are not aware of the existence of security vulnerabilities, so the device
configuration as provided by manufacturers will be retained by many users. Below are listed several
points which manufacturers should consider.
Remove debug mode
Phones are sometimes set in a debug mode during manufacturing, but this mode must be disabled
before the phone is sold. This mode allows access to different features, not intended for routine use by a
user. Due to the speed of development and production, distractions occur and some devices are sold in
debug mode. This kind of deployment exposes mobile devices to exploits that utilize this oversight.[54][55]
Default settings
When a smartphone is sold, its default settings must be correct, and not leave security gaps. The default
configuration is not always changed, so a good initial setup is essential for users. There are, for example,
default configurations that are vulnerable to denial of service attacks.[36][56]
Security audit of apps
Along with smart phones, appstores have emerged. A user finds themselves facing a huge range of
applications. This is especially true for providers who manage appstores because they are tasked with
examining the apps provided, from different points of view (e.g. security, content). The security audit
should be particularly cautious, because if a fault is not detected, the application can spread very quickly
within a few days, and infect a significant number of devices.[36]
Detect suspicious applications demanding rights
When installing applications, it is good to warn the user against sets of permissions that, grouped
together, seem potentially dangerous, or at least suspicious. Frameworks like such as Kirin, on Android,
attempt to detect and prohibit certain sets of permissions.[57]
Revocation procedures
Along with appstores appeared a new feature for mobile apps: remote revocation. First developed by
Android, this procedure can remotely and globally uninstall an application, on any device that has it. This
means the spread of a malicious application that managed to evade security checks can be immediately
stopped when the threat is discovered.[58][59]
Avoid heavily customized systems
Manufacturers are tempted to overlay custom layers on existing operating systems, with the dual
purpose of offering customized options and disabling or charging for certain features. This has the dual
effect of risking the introduction of new bugs in the system, coupled with an incentive for users to modify
the systems to circumvent the manufacturer's restrictions. These systems are rarely as stable and
reliable as the original, and may suffer from phishing attempts or other exploits.
Improve software patch processes
New versions of various software components of a smartphone, including operating systems, are
regularly published. They correct many flaws over time. Nevertheless, manufacturers often do not deploy
these updates to their devices in a timely fashion, and sometimes not at all. Thus, vulnerabilities persist
when they could be corrected, and if they are not, since they are known, they are easily exploitable.[57]
User awareness
Much malicious behavior is allowed by the carelessness of the user. From simply not leaving the device
without a password, to precise control of permissions granted to applications added to the smartphone,
the user has a large responsibility in the cycle of security: to not be the vector of intrusion. This
precaution is especially important if the user is an employee of a company that stores business data on
the device. Detailed below are some precautions that a user can take to manage security on a
A recent survey by internet security experts BullGuard showed a lack of insight into the rising number of
malicious threats affecting mobile phones, with 53% of users claiming that they are unaware of security
software for Smartphones. A further 21% argued that such protection was unnecessary, and 42%
admitted it hadn't crossed their mind ("Using APA," 2011). These statistics show consumers are not
concerned about security risks because they believe it is not a serious problem. The key here is to
always remember smartphones are effectively handheld computers and are just as vulnerable.
Being skeptical
A user should not believe everything that may be presented, as some information may be phishing or
attempting to distribute a malicious application. It is therefore advisable to check the reputation of the
application that they want to buy before actually installing it.[60]
Permissions given to applications
The mass distribution of applications is accompanied by the establishment of different permissions
mechaniSMS for each operating system. It is necessary to clarify these permissions mechaniSMS to
users, as they differ from one system to another, and are not always easy to understand. In addition, it is
rarely possible to modify a set of permissions requested by an application if the number of permissions is
too great. But this last point is a source of risk because a user can grant rights to an application, far
beyond the rights it needs. For example, a note taking application does not require access to the
geolocation service. The user must ensure the privileges required by an application during installation
and should not accept the installation if requested rights are inconsistent.[61][56][62]
Be careful
Protection of a user's phone through simple gestures and precautions, such as locking the smartphone
when it is not in use, not leaving their device unattended, not trusting applications, not storing sensitive
data, or encrypting sensitive data that cannot be separated from the device.[63][64]
Ensure data
Smartphones have a significant memory and can carry several gigabytes of data. The user must be
careful about what data it carries and whether they should be protected. While it is usually not dramatic if
a song is copied, a file containing bank information or business data can be more risky. The user must
have the prudence to avoid the transmission of sensitive data on a smartphone, which can be easily
stolen. Furthermore, when a user gets rid of a device, they must be sure to remove all personal data
These precautions are measures that leave no easy solution to the intrusion of people or malicious
applications in a smartphone. If users are careful, many attacks can be defeated, especially phishing and
applications seeking only to obtain rights on a device.
Centralized storage of text messages
One form of mobile protection allows companies to control the delivery and storage of text messages, by
hosting the messages on a company server, rather than on the sender or receiver's phone. When certain
conditions are met, such as an expiration date, the messages are deleted.[66]
Limitations of certain security measures
The security mechaniSMS mentioned in this article are to a large extent inherited from knowledge and
experience with computer security. The elements composing the two device types are similar, and there
are common measures that can be used, such as antivirus and firewall. However, the implementation
of these solutions is not necessarily possible or at least highly constrained within a mobile device. The
reason for this difference is the technical resources offered by computers and mobile devices: even
though the computing power of smartphones is becoming faster, they have other limitations than their
computing power.
Single-task system: Some operating systems, including some still commonly used, are single-
tasking. Only the foreground task is executed. It is difficult to introduce applications such as antivirus and
firewall on such systems, because they could not perform their monitoring while the user is operating the
device, when there would be most need of such monitoring.
Energy autonomy: A critical one for the use of a smartphone is energy autonomy. It is important
that the security mechaniSMS not consume battery resources, without which the autonomy of devices
will be affected dramatically, undermining the effective use of the smartphone.
Network Directly related to battery life, network utilization should not be too high. It is indeed one
of the most expensive resources, from the point of view of energy consumption. Nonetheless, some
calculations may need to be relocated to remote servers in order to preserve the battery. This balance
can make implementation of certain intensive computation mechaniSMS a delicate proposition.[67]
Furthermore, it should be noted that it is common to find that updates exist, or can be developed or
deployed, but this is not always done. One can, for example, find a user who does not know that there is
a newer version of the operating system compatible with the smartphone, or a user may discover known
vulnerabilities that are not corrected until the end of a long development cycle, which allows time to
exploit the loopholes.[55]
Next Generation of mobile security
There is expected to be four mobile environments that will make up the security framework:[68]
Rich operating system
In this category will fall traditional Mobile OS like Android, iOS, Symbian OS or Windows Phone. They
will provide the traditional functionality and security of an OS to the applications.
Secure Operating System (Secure OS)
A secure kernel which will run in parallel with a fully featured Rich OS, on the same processor core. It will
include drivers for the Rich OS ("normal world") to communicate with the secure kernel ("secure world").
The trusted infrastructure could include interfaces like the display or keypad to regions of PCI-E address
space and memories.
Trusted Execution Environment (TEE)
Made up of hardware and software. It helps in the control of access rights and houses sensitive
applications, which need to be isolated from the Rich OS. It effectively acts as a firewall between the
"normal world" and "secure world".
Secure Element (SE)
The SE consists of tamper resistant hardware and associated software. It can provide high levels of
security and work in tandem with the TEE. The SE will be mandatory for hosting proximity payment
applications or official electronic signatures.
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* Mr. Nikola Zlatanov spent over 20 years working in the Capital Semiconductor Equipment Industry. His work at Gasonics, Novellus,
Lam and KLA-Tencor involved progressing electrical engineering and management roles in disruptive technologies. Nikola received his
Undergraduate degree in Electrical Engineering and Computer Systems from Technical University, Sofia, Bulgaria and completed a
Graduate Program in Engineering Management at Santa Clara University. He is currently consulting for Fortune 500 companies as well
as Startup ventures in Silicon Valley, California.
... This Phishing attack is propositional to the exponential growth experienced in internet [1] and its usage, irrespective of the various detection approaches that have been modelled to checkmate phishing attack exploit. Phishing refers to the act of illegally exploiting the confidentiality of an entity, the breach of confidentiality includes but not limited to username, credit card details, password and personal profile of target victim unwittingly [2], [3]. Fig. 1 shows a typical phishing life circle. ...
... Phishing attack has increased tremendously over the years across the platform of computing as about 1.3 million malicious phishing site was discover in 2017 [5] ,these has led to a high false positive rate in terms of phishing attack detection which is a major setback in phishing detection likewise the level of accuracy achieved from classification algorithms, while phishing was tagged an attack that has been occurring in a ridiculous peace with evolving techniques that aids in concealing its heinous act to be executed unknowingly on target victim [6], phishing attack on smart devices have recorded a hit of 36% in 2015 [3] and 91% of cyber exploit was said to have been initiated through phish attack [7]. Financial institutions, social media, webmail, healthcare, ecommerce, software as a service, cloud storage/file hosting, government services, retailers, insurance firm, social network, dating site, as well as technology users are key target of phishing attack [6]. ...
Conference Paper
Full-text available
Exponential growth experienced in Internet usage have pave way to exploit users of the Internet, phishing attack is one of the means that can be used to obtained victim confidential details unwittingly across the Internet. A high false positive rate and low accuracy has been a setback in phishing detection. In this research RandomForest, SysFor, SPAARC, RepTree, RandomTree, LMT, ForestPA, JRip, PART, NNge, OneR, AdaBoostM1, RotationForest, LogitBoost, RseslibKnn, LibSVM, and BayesNet were employed to achieve the comparative analysis of machine classifier. The performance of the classifier algorithms were rated using Accuracy, Precision, Recall, F-Measure, Root Mean Squared Error, Receiver Operation Characteristics Area, Root Relative Squared Error False Positive Rate and True Positive Rate using WEKA data mining tool. The research revealed that quit a number of classifiers also exist which if properly explored will yield more accurate results for phishing detection. RondomForest was found to be an excellent classifier that gives the best accuracy of 0.9838 and a false positive rate of 0.017. The comparative analysis result indicates the achievement of low false positive rate for phishing classification which suggest that anti-phishing application developer can implement the machine learning classification algorithm that was discovered to be the best in this study to enhance the feature of phishing attack detection and classification.
This article investigates the possible benefits of complex system governance (CSG) as a foundation for enhancing cybersecurity in critical cyber-physical systems (CPS). CPS are intrinsically linked to cyberspace and vulnerable to a wide range of risks stemming from physical and cyber threats. There remains a lack of robust frameworks for addressing the issue of cybersecurity for CPS at the metasystem level. In response, the authors suggest CSG as an organizing construct capable of providing a greater degree of cohesion and as a means to provide for design, execution, and evolution of ‘metasystemic' functions necessary to provide for communication, control, and coordination, and integration is critical to the cybersecurity of CPS. In this article, CSG is introduced as a potential construct for enhancing cybersecurity in CPS. A hypothetical case study application is then provided to illustrate the potential for this research. Finally, the authors offer conclusions and suggest future research. Keywords Case Study, Complex System Governance, Cyber-Physical Systems, Management Cybernetics, Metasystem Function, Power Grid, Systems Thinking
Full-text available
This article presents an economic model that determines the optimal amount to invest to protect a given set of information. The model takes into account the vulnerability of the information to a security breach and the potential loss should such a breach occur. It is shown that for a given potential loss, a firm should not necessarily focus its investments on information sets with the highest vulnerability. Since extremely vulnerable information sets may be inordinately expensive to protect, a firm may be better off concentrating its efforts on information sets with midrange vulnerabilities. The analysis further suggests that to maximize the expected benefit from investment to protect information, a firm should spend at most a small fraction (1/e) of the expected loss due to a security breach.
Full-text available
This article presents an economic model that determines the optimal amount to invest to protect a given set of information. The model takes into account the vulnerability of the information to a security breach and the potential loss should such a breach occur. It is shown that for a given potential loss, a firm should not necessarily focus its investments on information sets with the highest vulnerability. Since extremely vulnerable information sets may be inordinately expensive to protect, a firm may be better off concentrating its efforts on information sets with midrange vulnerabilities. The analysis further suggests that to maximize the expected benefit from investment to protect information, a firm should spend only a small fraction of the expected loss due to a security breach.
Of all the recent large-scale data breaches, of which there have been many, the Ashley Madison ‘hack’ has attracted the most interest and the greatest number of column inches in the press. And it's not hard to see why: there is a prurient element in watching the personal details of people who have used a site dedicated to infidelity being exposed to public gaze. But it is significant in other ways, too – not least because of the sheer scale of the leak and the nature of the data, from payment card transactions to source code. Of all the recent large-scale data breaches, the Ashley Madison ‘hack’ has attracted the most interest and the greatest number of column inches in the press. There is a prurient element, but it is significant for simple technical reasons too – to do with the sheer scale of the leak and the nature of the data, from payment card transactions to source code. Steve Mansfield-Devine details the story as it has unfolded so far and examines some of the more significant aspects.
This article traces the origins of US government-sponsored computer security research and the path that led from a focus on government-funded research and system development to a focus on the evaluation of commercial products. That path led to the creation of the Trusted Computer System Evaluation Criteria (TCSEC), or Orange Book. The TCSEC placed great emphasis on requirements for mandatory security controls and high assurance, and the resulting TCSEC evaluation process was time-consuming and costly for commercial vendors and emphasized product features not valued by customers. As a result, vendor commitment to evaluations waned. The TCSEC was eventually supplanted by the international Common Criteria, which after almost 15 years, have moved to a model based on more straightforward requirements and a more deterministic evaluation process.
Conference Paper
Most security mechanisms proposed to date unquestioningly place trust in microprocessor hardware. This trust, however, is misplaced and dangerous because microprocessors are vulnerable to insider attacks that can catastrophically compromise security, integrity and privacy of computer systems. In this paper, we describe several methods to strengthen the fundamental assumption about trust in microprocessors. By employing practical, lightweight attack detectors within a microprocessor, we show that it is possible to protect against malicious logic embedded in microprocessor hardware. We propose and evaluate two area-efficient hardware methods - TrustNet and DataWatch - that detect attacks on microprocessor hardware by knowledgeable, malicious insiders. Our mechanisms leverage the fact that multiple components within a microprocessor (e.g., fetch, decode pipeline stage etc.) must necessarily coordinate and communicate to execute even simple instructions, and that any attack on a microprocessor must cause erroneous communications between micro architectural subcomponents used to build a processor. A key aspect of our solution is that TrustNet and DataWatch are themselves highly resilient to corruption. We demonstrate that under realistic assumptions, our solutions can protect pipelines and on-chip cache hierarchies at negligible area cost and with no performance impact. Combining TrustNet and DataWatch with prior work on fault detection has the potential to provide complete coverage against a large class of microprocessor attacks.
Conference Paper
As designs become more complex, formal verification techniques are becoming increasingly important in the hardware industry. Many different methods are used, ranging from propositional tautology checking up to use of interactive higher-order theorem provers. Our own work is mainly concerned with the formal verification of floating-point mathematical functions. As this paper illustrates, such applications require a rather general mathematical framework and the ability to automate special-purpose proof algorithms in a reliable way. Our work uses the public-domain interactive theorem prover HOL Light, and we claim that this and similar 'LCF-style' theorem provers are a good choice for such applications.
Mobile Security: A Guide for Users. Copper Horse Solutions Limited
  • David Rogers
Rogers, David (2013). Mobile Security: A Guide for Users. Copper Horse Solutions Limited. ISBN 978-1-291-53309-5.
Hacker says to show passenger jets at risk of cyber attack
  • Jim Finkle
Jim Finkle (4 August 2014). "Hacker says to show passenger jets at risk of cyber attack". Reuters.
Home Depot: 56 million cards exposed in breach
  • Melvin Backman
Melvin Backman (18 September 2014). "Home Depot: 56 million cards exposed in breach". CNN Money.