Chapter

GuidedPass: Helping Users to Create Strong and Memorable Passwords: 21st International Symposium, RAID 2018, Heraklion, Crete, Greece, September 10-12, 2018, Proceedings

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

Password meters and policies are currently the only tools helping users to create stronger passwords. However, such tools often do not provide consistent or useful feedback to users, and their suggestions may decrease memorability of resulting passwords. Passwords that are difficult to remember promote bad practices, such as writing them down or password reuse, thus stronger passwords do not necessarily improve authentication security. In this work, we propose GuidedPass – a system that suggests real-time password modifications to users, which preserve the password’s semantic structure, while increasing password strength. Our suggestions are based on structural and semantic patterns mined from successfully recalled and strong passwords in several IRB-approved user studies [30]. We compare our approach to password creation with creation under NIST [12] policy, Ur et al. [26] guidance, and zxcvbn password-meter. We show that GuidedPass outperforms competing approaches both in password strength and in recall performance.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... The textual password remains the most popular method for authenticating user access to computing systems and apps. There is a growing conflict between memorable textual passwords and their strength [21] occasionally referred to as the password strength and usability dilemma [3]. Indeed, password strength and recall are the key performance metrics underpinning a plethora of experiments spanning over two decades. ...
... Real-time password modification suggestions aim to preserve the password's semantic structure and increase password strength [21]. The suggestions are the result of data mining and machine learning from existing, more resilient, and easier to recall passwords in the database. ...
Chapter
The most popular form of user authentication for systems and services access is passwords. Integrated password policies strictly regulate the DNA of these passwords which presents a challenge for users to generate and remember strong passwords. Users prefer less memory burden and often devise simplistic passwords as far as the password regulation permits or resort to unsafe practices such as writing passwords on posits. Simultaneously successful password cracking attempts are rising at an alarming rate mostly due to users’ denial to render strong passwords and hackers’ increasingly potent technology. As a defense against password cracking and creating more resilient passwords, this study offers a novel encoded native name password. Native names that aren’t written in English will need to be manually encoded by the user aligning the encoded native names to the NIST guideline. According to the results of this study, encoded native name passwords are just as safe as randomly generated passwords. However, encoded native name passwords have an added advantage because users will not have to write down or save their passwords anywhere which can make them vulnerable to password cracking. Based on the experiments described in this study, encoded native name passwords with lengths of nine and ten characters took the longest time to crack compared to other forms of passwords.
Article
Supporting users with secure password creation is a well-explored yet unresolved research topic. A promising intervention is the password meter, i.e. providing feedback on the user's password strength as and when it is created. However, findings related to the password meter's effectiveness are varied. An extensive literature review revealed that, besides password feedback, effective password meters often include: (a) feedback nudges to encourage stronger passwords choices and (b) additional guidance. A between-subjects study was carried out with 645 participants to test nine variations of password meters with different types of feedback nudges exploiting various heuristics and norms. This study explored differences in resulting passwords: (1) actual strength, (2) memorability, and (3) user perceptions. The study revealed that password feedback, in combination with a feedback nudge and additional guidance, labelled a hybrid password meter, was generally more efficacious than either intervention on its own, on all three metrics. Yet, the type of feedback nudge targeting either the person, the password creation task, or the social context, did not seem to matter much. The meters were nearly equally efficacious. Future work should explore the long-term effects of hybrid password meters in real-life settings to confirm the external validity of these findings.
Article
Purpose The average employee spends a total of 18.6 h every two months on password-related activities, including password retries and resets. The problem is caused by the user forgetting or mistyping the password (usually because of character switching). The source of this issue is that while a password containing combinations of lowercase characters, uppercase characters, digits and special characters (LUDS) offers a reasonable level of security, it is complex to type and/or memorise, which prolongs the user authentication process. This results in much time being spent for no benefit (as perceived by users), as the user authentication process is merely a prerequisite for whatever a user intends to accomplish. This study aims to address this issue, passphrases that exclude the LUDS guidelines are proposed. Design/methodology/approach To discover constructs that create security and to investigate usability concerns relating to the memory and typing issues concerning passphrases, this study was guided by three theories as follows: Shannon’s entropy theory was used to assess security, chunking theory to analyse memory issues and the keystroke level model to assess typing issues. These three constructs were then evaluated against passwords and passphrases to determine whether passphrases better address the security and usability issues related to text-based user authentication. A content analysis was performed to identify common password compositions currently used. A login assessment experiment was used to collect data on user authentication and user – system interaction with passwords and passphrases in line with the constructs that have an impact on user authentication issues related to security, memory and typing. User–system interaction data was collected from a purposeful sample size of 112 participants, logging in at least once a day for 10 days. An expert review, which comprised usability and security experts with specific years of industry and/or academic experience, was also used to validate results and conclusions. All the experts were given questions and content to ensure sufficient context was provided and relevant feedback was obtained. A pilot study involving 10 participants (experts in security and/or usability) was performed on the login assessment website and the content was given to the experts beforehand. Both the website and the expert review content was refined after feedback was received from the pilot study. Findings It was concluded that, overall, passphrases better support the user during the user authentication process in terms of security, memory issues and typing issues. Originality/value This research aims at promoting the use of a specific type of passphrase instead of complex passwords. Three core aspects need to be assessed in conjunction with each other (security, memorisation and typing) to determine whether user-friendly passphrases can support user authentication better than passwords.
Chapter
This paper address the emergent need for training measures designed to improve user behavior in regards to security. We do this by proposing a framework for information security training that has been developed for several years and over several projects. The result is the framework ContextBased MicroTraining (CBMT) which provides goals and guidelines for how to better implement information security training that supports the user in the situation where the user needs support. CBMT has been developed and tested for use in higher education as well as for the support of users during passwords creation. This paper presents version 1.0 of the framework with the latest refinements.
Conference Paper
In the past, there have been several studies in analyzing password strength and structures. However, there are still many unknown questions to understand what really makes passwords both memorable and strong. In this work, we aim to answer some of these questions by analyzing password dataset through the lenses of data science and machine learning perspectives. We use memorable 3,260 password dataset collected from prior IRB-approved user studies over 3 years and classify passwords into three strength groups using online and offline attack limits. Then, we apply a tensor decomposition to analyze password dataset by constructing a 3rd-order tensor with passwords' syntactic and semantic features. In particular, we used PARAFAC2 tensor decomposition to uncover the main characteristics and features that affect password strength. We quantitatively identified the underlying factors that are more frequently observed in strong and memorable passwords. We hope that our finding can validate widely accepted advice for creating strong passwords and provide useful insights to design a better password suggestion system.
Technical Report
Full-text available
These guidelines provide technical requirements for federal agencies implementing digital identity services and are not intended to constrain the development or use of standards outside of this purpose. The guidelines cover identity proofing and authentication of users (such as employees, contractors, or private individuals) interacting with government IT systems over open networks. They define technical requirements in each of the areas of identity proofing, registration, authenticators, management processes, authentication protocols, federation, and related assertions. This publication supersedes NIST Special Publication 800-63-2.
Conference Paper
Full-text available
It is no secret that users have difficulty choosing and remembering strong passwords, especially when asked to choose different passwords across different accounts. While research has shed light on password weaknesses and reuse, less is known about user motivations for following bad password practices. Understanding these motivations can help us design better interventions that work with the habits of users and not against them. We present a comprehensive user study in which we both collect and analyze users' real passwords and the reasoning behind their password habits. This enables us to contrast the users' actual behaviors with their intentions. We find that user intent often mismatches practice, and that this, coupled with some misconceptions and convenience, fosters bad password habits. Our work is the first to show the discrepancy between user intent and practice when creating passwords, and to investigate how users trade off security for memorability.
Conference Paper
Full-text available
Despite their ubiquity, many password meters provide inaccurate strength estimates. Furthermore, they do not explain to users what is wrong with their password or how to improve it. We describe the development and evaluation of a data-driven password meter that provides accurate strength measurement and actionable, detailed feedback to users. This meter combines neural networks and numerous carefully combined heuristics to score passwords and generate data-driven text feedback about the user's password. We describe the meter's iterative development and final design. We detail the security and usability impact of the meter's design dimensions, examined through a 4,509-participant online study. Under the more common password-composition policy we tested, we found that the data-driven meter with detailed feedback led users to create more secure, and no less memorable, passwords than a meter with only a bar as a strength indicator.
Conference Paper
Full-text available
Modern password guessing attacks adopt sophisticated probabilistic techniques that allow for orders of magnitude less guesses to succeed compared to brute force. Unfortunately, best practices and password strength evaluators failed to keep up: they are generally based on heuristic rules designed to defend against obsolete brute force attacks. Many passwords can only be guessed with significant effort, and motivated attackers may be willing to invest resources to obtain valuable passwords. However, it is eminently impractical for the defender to simulate expensive attacks against each user to accurately characterize their password strength. This paper proposes a novel method to estimate the number of guesses needed to find a password using modern attacks. The proposed method requires little resources, applies to a wide set of probabilistic models, and is characterised by highly desirable convergence properties. The experiments demonstrate the scalability and generality of the proposal. In particular, the experimental analysis reports evaluations on a wide range of password strengths, and of state-of-the-art attacks on very large datasets, including attacks that would have been prohibitively expensive to handle with existing simulation-based approaches.
Conference Paper
Full-text available
To encourage strong passwords, system administrators employ password-composition policies, such as a traditional policy requiring that passwords have at least 8 characters from 4 character classes and pass a dictionary check. Recent research has suggested, however, that policies requiring longer passwords with fewer additional requirements can be more usable and in some cases more secure than this traditional policy. To explore long passwords in more detail, we conducted an online experiment with 8,143 participants. Using a cracking algorithm modified for longer passwords, we evaluate eight policies across a variety of metrics for strength and usability. Among the longer policies, we discover new evidence for a security/usability tradeoff, with none being strictly better than another on both dimensions. However, several policies are both more usable and more secure that the traditional policy we tested. Our analyses additionally reveal common patterns and strings found in cracked passwords. We discuss how system administrators can use these results to improve password-composition policies.
Conference Paper
Full-text available
To help users create stronger text-based passwords, many web sites have deployed password meters that provide visual feedback on password strength. Although these meters are in wide use, their effects on the security and usability of passwords have not been well studied. We present a 2,931-subject study of password creation in the presence of 14 password meters. We found that meters with a variety of visual appearances led users to create longer passwords. However, significant increases in resistance to a password-cracking algorithm were only achieved using meters that scored passwords stringently. These stringent meters also led participants to include more digits, symbols, and uppercase letters. Password meters also affected the act of password creation. Participants who saw stringent meters spent longer creating their password and were more likely to change their password while entering it, yet they were also more likely to find the password meter annoying. However, the most stringent meter and those without visual bars caused participants to place less importance on satisfying the meter. Participants who saw more lenient meters tried to fill the meter and were averse to choosing passwords a meter deemed "bad" or "poor." Our findings can serve as guidelines for administrators seeking to nudge users towards stronger passwords.
Conference Paper
Full-text available
Text-based passwords remain the dominant authentication method in computer systems, despite significant advancement in attackers' capabilities to perform password cracking. In response to this threat, password composition policies have grown increasingly complex. However, there is insufficient research defining metrics to characterize password strength and using them to evaluate password-composition policies. In this paper, we analyze 12,000 passwords collected under seven composition policies via an online study. We develop an efficient distributed method for calculating how effectively several heuristic password-guessing algorithms guess passwords. Leveraging this method, we investigate (a) the resistance of passwords created under different conditions to guessing, (b) the performance of guessing algorithms under different training sets, (c) the relationship between passwords explicitly created under a given composition policy and other passwords that happen to meet the same requirements, and (d) the relationship between guess ability, as measured with password-cracking algorithms, and entropy estimates. Our findings advance understanding of both password-composition policies and metrics for quantifying password security.
Article
Full-text available
"We're secure! We use passwords!" How many of us have heard this claim? Or even -- "We're secure! We have a password policy!" Using a password or having a password policy in today's world of computing is not enough. Passwords provide a first line of defense in most cases, but there is much more. "A recent survey by Rainbow Technologies Inc. indicates that the use of insecure passwords can be costly -- and potentially risky -- for corporate data. "[Rosencrance] This paper focuses on the use of passwords and password policy and looks at the good, the bad and the ugly scenarios that arise.
Conference Paper
Full-text available
HCI research published 10 years ago pointed out that many users cannot cope with the number and complexity of passwords, and resort to insecure workarounds as a consequence. We present a study which re-examined password policies and password practice in the workplace today. 32 staff members in two organisations kept a password diary for 1 week, which produced a sample of 196 passwords. The diary was followed by an interview which covered details of each password, in its context of use. We find that users are in general concerned to maintain security, but that existing security policies are too inflexible to match their capabilities, and the tasks and contexts in which they operate. As a result, these password policies can place demands on users which impact negatively on their productivity and, ultimately, that of the organisation. We conclude that, rather than focussing password policies on maximizing password strength and enforcing frequency alone, policies should be designed using HCI principles to help the user to set an appropriately strong password in a specific context of use.
Conference Paper
Full-text available
Text-based passwords are the most common mechanism for authenticating humans to computer systems. To prevent users from picking passwords that are too easy for an adversary to guess, system administrators adopt password-composition policies (e.g., requiring passwords to contain symbols and numbers). Unfortunately, little is known about the relationship between password-composition policies and the strength of the resulting passwords, or about the behavior of users (e.g., writing down passwords) in response to different policies. We present a large-scale study that investigates password strength, user behavior, and user sentiment across four password-composition policies. We characterize the predictability of passwords by calculating their entropy, and find that a number of commonly held beliefs about password composition and strength are inaccurate. We correlate our results with user behavior and sentiment to produce several recommendations for password-composition policies that result in strong passwords without unduly burdening users.
Conference Paper
Full-text available
Text-based passwords are still the most commonly used authentication mechanism in information systems. We took advantage of a unique opportunity presented by a significant change in the Carnegie Mellon University (CMU) computing services password policy that required users to change their passwords. Through our survey of 470 CMU computer users, we collected data about behaviors and practices related to the use and creation of passwords. We also captured users' opinions about the new, stronger policy requirements. Our analysis shows that, although most of the users were annoyed by the need to create a complex password, they believe that they are now more secure. Furthermore, we perform an entropy analysis and discuss how our findings relate to NIST recommendations for creating a password policy. We also examine how users answer specific questions related to their passwords. Our results can be helpful in designing better password policies that consider not only technical aspects of specific policy rules, but also users' behavior in response to those rules.
Article
What can a human compute in his/her head that a powerful adversary cannot infer? To answer this question, we define a model of human computation and a measure of security. Then, motivated by the special case of password creation, we propose a collection of well-defined password-generation methods. We show that our password generation methods are humanly computable and, to a well-defined extent, machine uncrackable. For the proof of security, we posit that password generation methods are public, but that the human’s privately chosen seed is not, and that the adversary will have observed only a few input-output pairs. Besides the application to password generation, our proposed Human Usability Model (HUM) will have other applications.
Conference Paper
Passwords are widely used for user authentication, but they are often difficult for a user to recall, easily cracked by automated programs and heavily reused. Security questions are also used for secondary authentication. They are more memorable than passwords, but are very easily guessed. We propose a new authentication mechanism, called "life-experience passwords (LEPs)," which outperforms passwords and security questions, both at recall and at security. Each LEP consists of several facts about a user-chosen past experience, such as a trip, a graduation, a wedding, etc. At LEP creation, the system extracts these facts from the user's input and transforms them into questions and answers. At authentication, the system prompts the user with questions and matches her answers with the stored ones. In this paper we propose two LEP designs, and evaluate them via user studies. We further compare LEPs to passwords, and find that: (1) LEPs are 30--47 bits stronger than an ideal, randomized, 8-character password, (2) LEPs are up to 3x more memorable, and (3) LEPs are reused half as often as passwords. While both LEPs and security questions use personal experiences for authentication, LEPs use several questions, which are closely tailored to each user. This increases LEP security against guessing attacks. In our evaluation, only 0.7% of LEPs were guessed by friends, while prior research found that friends could guess 17--25% of security questions. LEPs also contained a very small amount of sensitive or fake information. All these qualities make LEPs a promising, new authentication approach.
Article
Enterprises that impose stringent password-composition policies appear to suffer the same fate as those that do not.
Article
Password-composition policies are the result of service providers becoming increasingly concerned about the security of online accounts. These policies restrict the space of user-created passwords to preclude easily guessed passwords and thus make passwords more difficult for attackers to guess. However, many users struggle to create and recall their passwords under strict password-composition policies, for example, ones that require passwords to have at least eight characters with multiple character classes and a dictionary check. Recent research showed that a promising alternative was to focus policy requirements on password length instead of on complexity. In this work, we examine 15 password policies, many focusing on length requirements. In doing so, we contribute the first thorough examination of policies requiring longer passwords. We conducted two online studies with over 20,000 participants, and collected both usability and password-strength data. Our findings indicate that password strength and password usability are not necessarily inversely correlated: policies that lead to stronger passwords do not always reduce usability. We identify policies that are both more usable and more secure than commonly used policies that emphasize complexity rather than length requirements. We also provide practical recommendations for service providers who want their users to have strong yet usable passwords.
Conference Paper
In this paper, we introduce an open-source and modular password analysis and research system, PARS, which provides a uniform, comprehensive and scalable research platform for password security. To the best of our knowledge, PARS is the first such system that enables researchers to conduct fair and comparable password security research. PARS contains 12 state-of-the-art cracking algorithms, 15 intra-site and cross-site password strength metrics, 8 academic password meters, and 15 of the 24 commercial password meters from the top-150 websites ranked by Alexa. Also, detailed taxonomies and large-scale evaluations of the PARS modules are presented in the paper.
Conference Paper
Password meters tell users whether their passwords are "weak" or "strong." We performed a laboratory experiment to examine whether these meters influenced users' password selections when they were forced to change their real passwords, and when they were not told that their passwords were the subject of a study. We observed that the presence of meters yielded significantly stronger passwords. We performed a followup field experiment to test a different scenario: creating a password for an unimportant account. In this scenario, we found that the meters made no observable difference: participants simply reused weak passwords that they used to protect similar low-risk accounts. We conclude that meters result in stronger passwords when users are forced to change existing passwords on "important" accounts and that individual meter design decisions likely have a marginal impact.
Article
Web surveys appear to be attaining lower response rates than equivalent mail surveys. One reason may be that there is currently little information on effective strategies for increasing response to Internet-based surveys. Web users are becoming more impatient with high-burden Web interactions. The authors examined the decision to respond to a Web survey by embedding a series of experiments in a survey of students at the University of Michigan. A sample of over 4,500 students was sent an e-mail invitation to participate in a Web survey on affirmative action policies. Methodological experiments included using a progress indicator, automating password entry, varying the timing of reminder notices to nonrespondents, and using a prenotification report of the anticipated survey length. Each of these experiments was designed to vary the burden (perceived or real) of the survey request. Results of these experiments are presented.
Article
Given the increasing number of bilinguals around the world, bilingual aphasia has become a hot topic in the field of clinical and theoretical research in communication sciences. The aim of this article is to provide data-driven cues for intervention with bilingual aphasia. First, the impact of a number of factors considered to influence second language processing will be discussed with reference to neurolinguistic and neuroimaging data. The discussion will then move to bilingual aphasia. Specifically, we shall describe the recovery patterns following bilingual aphasia, and discuss the issues of pathological mixing and switching. The literature and clinical evidence will provide the framework for a discussion of data-driven cues for intervention with bilingual aphasia.
Conference Paper
We examine the password policies of 75 dierent web- sites. Our goal is understand the enormous diversity of requirements: some will accept simple six-character passwords, while others impose rules of great complex- ity on their users. We compare dierent features of the sites to nd which characteristics are correlated with stronger policies. Our results are surprising: greater security demands do not appear to be a factor. The size of the site, the number of users, the value of the assets protected and the frequency of attacks show no correlation with strength. In fact we nd the reverse: some of the largest, most attacked sites with greatest assets allow relatively weak passwords. Instead, we nd that those sites that accept advertising, purchase spon- sored links and where the user has a choice show strong inverse correlation with strength. We conclude that the sites with the most restrictive password policies do not have greater security concerns, they are simply better insulated from the consequences of poor usability. Online retailers and sites that sell ad- vertising must compete vigorously for users and trac. In contrast to government and university sites, poor us- ability is a luxury they cannot aord. This in turn sug- gests that much of the extra strength demanded by the more restrictive policies is superuous: it causes con- siderable inconvenience for negligible security improve- ment.
Today i am releasing ten million passwords
  • M Burnett
Towards reliable storage of 56-bit secrets in human memory
  • J Bonneau
  • S E Schechter
zxcvbn: low-budget password strength estimation
  • D L Wheeler
Leveraging semantic transformation to investigate password habits and their causes
  • A Hanesamgar
  • K C Woo
  • J Mirkovic
Telepathwords: preventing weak passwords by reading users’ minds
  • S Komanduri
  • R Shay
  • L F Cranor
  • C Herley
  • S E Schechter