Password Managers in Digital Forensics

Abstract: Digital forensics – the scientific process to draw evidence from digital devices confiscated in a criminal investigation – is constantly adapting to technological changes. A current challenge is the widespread use of encryption that makes classical data retrieval methods obsolete. Relevant data must now be retrieved from running devices and without delay, ideally directly at the time of seizure. This requires standardised processes and specialised tools to ensure no data is overlooked, that forensic integrity is maintained, and that encrypted data can be successfully made available to investigators. While research produced many promising results in this field in the last years, there is still much work to be done due to countless different applications, operating systems, and devices that all behave in different ways. This thesis addresses a software category called password managers – applications that store login credentials to different services. Despite the obvious value of password manager data to a criminal investigation, a comprehensive description of a forensic process on how to extract such data has not yet been in the focus of research. The present work addresses this gap and presents a process to extract forensically relevant data from two password manager applications – Bitwarden and KeePass – by extending an existing forensic framework called Vision. Using design science, a forensic extraction process was developed by thoroughly analysing the inner workings of the mentioned password managers. The artefact was named Password Manager Forensics (PMF) and consists of a four-step extraction process with different Python modules to automate the extraction of relevant data. PMF was tested against three scenarios in a laboratory setting to evaluate its applicability in an investigative context. The results show that the artefact is able to extract forensically relevant information related to password managers that would otherwise not be readily available to investigators. PMF is capable to identify and extract relevant files, to extract master passwords from a memory dump, to parse configuration files for relevant data, to brute-force master passwords and PIN codes, to decrypt, extract, and validate password manager vault data, and to create summary reports. PMF is the first comprehensive forensic process to extract relevant data from password managers. This brings new opportunities for digital forensics examiners and a potential to improve the handling of devices that contain password manager data in digital investigations. The current version of PMF only supports Windows desktop applications of Bitwarden and KeePass. Yet, due to the open and flexible architecture of the artefact, further expansion and improvement is possible in future research.