SSD Forensics 2014. Recovering Evidence from SSD Drives: Understanding TRIM, Garbage Collection and Exclusions
We published an article on SSD forensics in 2012. SSD self-corrosion, TRIM and garbage collection were little known and poorly understood phenomena at that time, while encrypting and compressing SSD controllers were relatively uncommon. In 2014, many changes happened. We processed numerous cases involving the use of SSD drives and gathered a lot of statistical data. We now know more about many exclusions from SSD self-corrosion that allow forensic specialists to obtain more information from SSD drives.
Several years ago, Solid State drives (SSD) introduced a challenge to digital forensic specialists. Forensic acquisition of computers equipped with SSD storage became very different compared to acquisition of traditional hard drives. Instead of straightforward and predictable recovery of evidence, we are in the waters of stochastic forensics with SSD drives, where nothing can be assumed as a given.
With even the most recent publications not going beyond introducing the TRIM command and making a conclusion on SSD self-corrosion, it has been common knowledge - and a common misconception, - that deleted evidence cannot be extracted from TRIM-enabled SSD drives, due to the operation of background garbage collection.