Umit Karabiyik

Purdue University West Lafayette | Purdue · Department of Computer and Information Technology (IT)

Wearable devices are becoming increasingly popular, diverse, and accessible. To put it in perspective, in 2022 alone, more than 490 million wearable devices were sold. The diversity of wearables is beneficial to users but poses challenges for mobile forensic investigators. These devices track, utilize, and collect a wide range of user information,...

Crime linkage is the process of analyzing criminal behavior data to determine whether a pair or group of crime cases are connected or belong to a series of offenses. This domain has been extensively studied by researchers in sociology, psychology, and statistics. More recently, it has drawn interest from computer scientists, especially with advance...

Governments and law enforcement agencies (LEAs) are increasingly concerned about growing illicit activities in cyberspace, such as cybercrimes, cyberespionage, cyberterrorism, and cyberwarfare. In the particular context of cyberterrorism, hostile social manipulation (HSM) represents a strategy that employs different manipulation methods, mostly thr...

As the popularity of virtual reality (VR) applications increases, there is a growing concern for the forensic aspect of privacy and security of user data. This paper aims to investigate the extent to which forensically relevant user data can be recovered from Oculus Quest 2, specifically, from four social community applications: Horizon Worlds, Mul...

WeChat is one of the most popular instant messaging applications in the world. In 2021, WeChat had 1.24 billion active users. Its users call it ‘super app’ due to its various functions, and they particularly enjoy the payment feature for both personal and business purposes. Criminals abused the platforms to facilitate illegal activities such as ban...

An increasing number of companies have adopted online telecommunication software for their office software pack, and Webex was one of the popular choices. With the surging usage of online telecommunication software, online meeting exploitation and disruptions cases also increased. However, there is limited research performed on online telecommunica...

The United States prison system faces staggering levels of recidivism – the observed phenomenon wherein justice-involved individuals (JII) on parole are re-convicted and entered back into correctional facilities. Combined with the large existing prison population, this leads to an overtaxing of the human resources available for JII management and a...

The emergence of the Internet of Things technologies and the increase and convenience of smart home devices have contributed to the growth of self-installed home security systems. While home security devices have become more accessible and can help users monitor and secure their homes, they can also become targets of cyberattacks and/or witnesses o...

Microsoft released a new communication platform, Microsoft Teams, in 2017. Due in part to COVID-19, the popularity of communication platforms, like Microsoft Teams, increased exponentially. Given its user base and increased popularity, it seems likely that digital forensic investigators will encounter cases where Microsoft Teams is a relevant compo...

Constant advancements in technology have a significant impact on our everyday lives and the ecosystem in which we live. The growing popularity of cryptocurrencies (e.g., Bitcoin and Ethereum), along with Non-Fungible Tokens (NFTs), which are founded on blockchain technology, has opened the way for these blockchain projects to be integrated into a w...

Wearable devices are becoming more and more prevalent in our daily lives as people become more curious about how well they are doing in monitoring, improving, or maintaining their health and fitness. Fitness trackers and smartwatches have become almost ubiquitous, so these devices have begun to play a critical role in forensic investigations. In th...

TikTok has consistently been one of the most used mobile apps worldwide on any mobile operating system. However, despite people’s enjoyment of using the application, there have been growing concerns about the application’s origins and alleged privacy violations. These allegations have become such a big problem that the former President of the Unite...

Mobile devices, specifically smartphones, have become a necessity in everyday life, as we perform many essential day-to-day tasks using these devices. With the projected increase in mobile devices to 18.22 billion by 2025, the reliance on smartphones will only grow. This demand for smartphones has allowed various companies to start developing their...

In the digital forensics discipline, the lack of comprehensive research that addresses investigative challenges and opportunities for newer mobile Operating Systems (OSs) such as Android and iOS keeps continuing. These two OSs are currently widely operated by millions of smartphones and used by millions of users; therefore, forensic investigators n...

Rapid technology advancements, especially in the past decade, have allowed off-the-shelf unmanned aerial vehicles (UAVs) that weigh less than 250 g to become available for recreational use by the general population. Many well-known manufacturers (e.g., DJI) are now focusing on this segment of UAVs, and the new DJI Mini 2 drone is one of many that f...

The raising accessibility of Unmanned Aerial Vehicles (UAVs), colloquially known as drones, is rapidly increasing. Recent studies have discussed challenges that may come in tow with the growing use of this technology. These studies note that in-depth examination is required, especially when addressing challenges that carry a high volume of software...

Unmanned Aerial Vehicles (UAVs) also known as drones have created many challenges to the digital forensic field. These challenges are introduced in all processes of the digital forensic investigation (i.e., identification, preservation, examination, documentation, and reporting). From identification of evidence to reporting, there are several chall...

The technology used in drones is similar or identical across drone types and components, with many common risks and opportunities. The purpose of this study is to enhance the risk assessment procedures for Drone as a Service (DaaS) capabilities. STRIDE is an acronym that includes the following security risks: Spoofing, Tampering, Repudiation, Infor...

New smartphones made by small companies enter the technology market everyday. These new devices introduce new challenges for mobile forensic investigators as these devices end up becoming pertinent evidence during an investigation. One such device is the PinePhone from Pine Microsystems (Pine64). These new devices are sometimes also shipped with OS...

The raising accessibility of Unmanned Aerial Vehicles (UAVs), colloquially known as drones, is rapidly increasing. Drones have pros and cons like any other technologies that operate on different communication protocols (i.e., Network, Bluetooth, Satellite, etc.). Recent studies have discussed challenges that may come in tow with the growing use of...

Proliferation of digital platforms specifically Instant Messaging Applications (IMAs), have introduced new challenges to digital forensic investigations. With the rapidly increased use of WhatsApp application, it is plausible to speculate that WhatsApp became a potential source of threat and/or cybercrime. Some newly added features on WhatsApp, suc...

SailfishOS is a Linux kernel-based embedded device operation system, mostly deployed on cell phones. Currently, there is no sufficient research in this space, and at the same time, this operating system is gaining popularity, so it is likely for investigators to encounter it in the field. This paper focuses on mapping the digital artifacts pertinen...

In digital agriculture, the cognitive radio technology is being envisaged as solution to spectral shortage problems by allowing agricultural cognitive users to co-exist with PU in the same spectrum on the field. Cognitive radios increase system capacity and spectral efficiency by sensing the spectrum and adapting the transmission parameters. This d...

Threats from drones are becoming an increasing security concern throughout the U.S. and worldwide. No current standards exist for the manufacture and operation of counter unmanned aerial system technology, making it difficult to determine effective systems and components for specific uses. Current policy within the U.S. makes unmanned aerial system...

The increase in the adoption of wearable fitness trackers has led to their inclusion as valuable evidence used by law enforcement during investigations. The information available in these fitness trackers can be used by law enforcement to prosecute or exonerate an individual. Wearable fitness devices are constantly being released by companies, with...

Files in the backup of iOS devices can be a potential source of evidentiary data. Particularly, the iOS backup (obtained through a logical acquisition technique) is widely used by many forensic tools to sift through the data. A significant challenge faced by several forensic tool developers is the changes in the data organization of the iOS backup....

Digital forensic investigations are getting harder and more time consuming everyday because of various problems including rapid advances in technology, wide variety of available devices in investigations, and large amount of data to be analyzed. In order to tackle with these issues, digital forensic tools are developed by open-source communities an...

Validation is the scientifically accepted methodology for demonstrating the accuracy and reliability of a process. Currently, digital forensics discipline does not conduct the sort of validation testing needed to develop statistical confidence in tool performance, or to generate the empirical data needed to bring objectivity to examiner conclusions...

This paper presents the basic functionalities of a virtual reality framework developed for training first responders and digital forensic investigators. The framework is divided into two modules: training and evaluation. The framework provides a variety of functionalities and behaviors that can be assigned to virtual objects and allows training and...

In the last decade, wireless sensor networks (WSNs) and Internet-of-Things (IoT) devices are proliferated in many domains including critical infrastructures such as energy, transportation and manufacturing. Consequently, most of the daily operations now rely on the data coming from wireless sensors or IoT devices and their actions. In addition, per...

Smartphones contain large amounts of data that are of significant interest in forensic investigations. In many situations, a smartphone owner may be willing to provide a forensic investigator with access to data under a documented consent agreement. However, for privacy or personal reasons, not all the smartphone data may be extracted for analysis....

The rapid pace of invention in technology and the evolution of network communication has produced a new lifestyle with variety of opportunities and challenges. Remotely Piloted Aerial Systems (RPAS) technology, which includes drones, is one example of a recently invented technology that requires the collection of a solid body of defensible and admi...

Location sharing applications are becoming increasingly common. These applications allow users to share their own locations and view contacts' current locations on a map. Location applications are commonly used by friends and family members to view Global Positioning System (GPS) location of an individual, but valuable forensic evidence may exist i...

According to the Federal Aviation Administration (FAA), the number of Remotely Piloted Air Systems (RPASs), colloquially known as drones, will rapidly increase in the near future. Challenges with drones are focused not only on the security of these devices, but also on the criminal uses for drones which need to be carefully considered. Incident res...

WhatsApp is the most popular instant messaging application worldwide. Since 2016, users can send and receive messages through desktop clients, either through the WhatsApp desktop application or the web client accessible from supported web browsers. The author identified a gap in the literature in terms of WhatsApp forensics for desktop and web clie...

In digital agriculture, the cognitive radio technology is being envisaged as solution to spectral shortage problems by allowing agricultural cognitive users to co-exist with non-cognitive users in the same spectrum on the field. Cognitive radios increase system capacity and spectral efficiency by sensing the spectrum and adapting the transmission p...

The amount of data stored on smart phones and other mobile devices has increased phenomenally over the last decade. As a result there has been a spike in the use of these devices for documenting different scenarios that are encountered by the users as they go about their daily lives. In many situations, for example, in cases of accidents, malicious...

In the last decade, wireless sensor networks (WSNs) and Internet-of-Things (IoT) devices are proliferated in many domains including critical infrastructures such as energy, transportation and manufacturing. Consequently, most of the daily operations now rely on the data coming from wireless sensors or IoT devices and their actions. In addition, per...

Digital forensic laboratory is indispensable in supporting the investigative process and performing forensically sound investigations. In order to perform efficient investigations, the laboratory must be designed properly. Hence, purchase of proper yet expensive the hardware and software equipment is necessary. In this paper, we demonstrate that La...

On-road emergencies necessitates the availability of the patient’s medical records to the emergency centers for better treatment. However, these medical records are often encrypted to preserve the patient’s privacy. Revealing the secret key used to encrypt these records to the emergency center would not only give unlimited unauthorized future acces...

As the geolocation capabilities of smartphones continue to improve, developers have continued to create more innovative applications that rely on this location information for their primary function. This can be seen with Niantic’s release of Pokémon GO, which is a massively multiplayer online role playing and augmented reality game. This game beca...

As the geolocation capabilities of smartphones continue to improve, developers have continued to create more innovative applications that rely on this location information for their primary function. This can be seen with Niantic's release of Pokémon GO, which is a massively multiplayer online role playing and augmented reality game. This game beca...

Social networks in any form, specifically online social networks (OSNs), are becoming a part of our everyday life in this new millennium especially with the advanced and simple communication technologies through easily accessible devices such as smartphones and tablets. The data generated through the use of these technologies need to be analyzed fo...

Online social network analysis has attracted great attention with a vast number of users sharing information and availability of APIs that help to crawl online social network data. In this paper, we study the research studies that are helpful for user characterization as online users may not always reveal their true identity or attributes. We espec...

It is a very likely situation for a digital forensics investigator to encounter a virtual machine during an investigation. The evidence found in a vmdk disk may not necessarily belong to the virtual machine. It is possible that a vmdk disk could contain previously deleted data from the host machine. In this paper we investigate the possibility of t...

Digital forensics investigators need specialized tools in order to retrieve evidence on hard disks. When using automated tools, only conventional areas of the disk are often analyzed and as a result potential evidence in hidden areas may be missed. One reason for this is the lack of a universal standard or approach with regards to the systematic di...

Open source software tools designed for disk analysis play a critical role in today's forensic investigations. These tools typically are onerous to use and rely on expertise both in investigation techniques as well as in the tools and disk structures. In previous work we presented the design and initial development for a toolkit that can be used as...

Software tools designed for disk analysis play a critical role today in digital forensics investigations. However, these digital forensics tools are often difficult to use, usually task specific, and generally require professionally trained users with IT backgrounds. The relevant tools are also often open source requiring additional technical knowl...

This chapter presents a solution to the problem of identifying passwords on storage media. Because of the proliferation of websites for finance, commerce and entertainment, the typical user today often has to store passwords on a computer hard drive. The identification problem is to find strings on the disk that are likely to be passwords. Automate...

Open source software tools designed for disk analysis play a critical role in today's forensic investigations. These tools typically are onerous to use and rely on expertise both in investigation techniques as well as in the tools and disk structures. In previous work we presented the design and initial development for a toolkit that can be used as...