The paper “How Cuckoo filter can improve existing approximate matching techniques” got accepted at the 7th International Conference on Digital Forensics & Cyber Crime (ICDF2C’15).
Furthermore, I will present the article “Watch what you wear: Preliminary forensic analysis of smart watches” at Availability, Reliability, and Security (ARES’15, IEEE) in Toulouse, France in August.
Both abstracts are below.
Thank you to all co-Authors who put a tremendous amount of effort in these papers.
How Cuckoo filter can improve existing approximate matching techniques
In recent years, approximate matching algorithms have become an important component in digital forensic research and have been adopted in some other working areas as well. Currently there are several approaches but especially sdhash and mrsh-v2 attract the attention of the community because of their good overall performance (runtime, compression and detection rates). Although both approaches have a quite different proceeding, their final output (the similarity digest) is very similar as both utilize Bloom filters. This data structure was presented in 1970 and thus has been around for a while. Recently, a new data structure was proposed and claimed to be faster and have a smaller memory footprint than Bloom filter -- Cuckoo filter.
In this paper we analyze the feasibility of Cuckoo filter for approximate matching algorithms and present a prototype implementation called mrsh-cf which is based on a special version of mrsh-v2 called mrsh-net. We demonstrate that by using Cuckoo filter there is a runtime improvement of approximately 37% and also a significantly better false positive rate. The memory footprint of mrsh-cf is 8 times smaller than mrsh-net, while the compression rate is twice than Bloom filter based fingerprint.
Watch what you wear: Preliminary forensic analysis of smart watches
This work presents preliminary forensic analysis of two popular smart watches, the Samsung Gear 2 Neo and LG G. These wearable computing devices have the form factor of watches and sync with smart phones to display notifications, track footsteps and record voice messages. We posit that as smart watches are adopted by more users, the potential for them becoming a haven for digital evidence will increase thus providing utility for this preliminary work. In our work, we examined the forensic artifacts that are left on a Samsung Galaxy S4 Active phone that was used to sync with the Samsung Gear 2 Neo watch and the LG G watch. We further outline a methodology for physically acquiring data from the watches after gaining root access to them. Our results show that we can recover a swath of digital evidence directly form the watches when compared to the data on the phone that is synced with the watches. Furthermore, to root the LG G watch, the watch has to be reset to its factory settings which is alarming because the process may delete data of forensic relevance. Although this method is forensically intrusive, it may be used for acquiring data from already rooted LG watches. It is our observation that the data at the core of the functionality of at least the two tested smart watches, messages, health and fitness data, e-mails, contacts, events and notifications are accessible directly from the acquired images of the watches, which affirms our claim that the forensic value of evidence from smart watches is worthy of further study and should be investigated both at a high level and with greater specificity and granularity.