Wednesday, June 08, 2016

Updates

RegRipper Plugin Updates
I recently released some updates to RegRipper plugins, fixing code (IAW Eric's recent post) and releasing a couple of new plugins.  As such, I thought it might be helpful to share a bit about how the plugins might be used during an exam.

lastloggedon.pl - honestly, I'm not entirely sure how I'd use this plugin during analysis, beyond using it to document basic information about the system.

shimcache.pl - I can see using this plugin for just about any engagement where the program execution category of artifacts is of interest.  Remember the blog post about creating an analysis matrix?  If not, think malware detection, data exfil, etc.  As Eric mentioned in his recent webcast, you could use indicators you find in the ShimCache data to pivot to other data sources, such as the AmCache.hve file, Prefetch files, Windows Event Log records with sources such as "Service Control Manager" in a timeline, etc.  However, the important thing to keep in mind is the context of the time stamps associated with each file entry...follow the data, don't force it to fit your theory.

Specific things I'd look for when parsing the ShimCache data include entries in the root of the Recycle Bin, the root of the user's profile, the root of the user's AppData/Roaming and Desktop folders, in C:\ProgramData, and with a UNC path (i.e., UNC\\tsclient\...).  Clearly, that's not all I'd look for, but those are definitely things I'd look for and be very interested in.  At one point, I'd included "alerts" in the output of some plugins that would automatically look for this sort of thing and alert the analyst to their presence, but there didn't seem to be a great deal of interest in this sort of thing. 

Win10 Notification DB
During his recent webcast regarding the AmCache.hve file, Eric mentioned the SwiftForensics site a couple of times.  Well, it turns out that Yogesh has been on to other things since he posted about the AmCache.hve file...he recently posted a structure description for the Windows 10 Notification database.  Yogesh also included a Python script for parsing the notification database...if you're examining Windows 10 systems, you might want to check it out.

I don't have enough experience yet examining Windows 10 systems to know what sorts of things would be of value, but I can imagine that there would be considerable value in this data, in a case where the user claimed to not have received an email, only to have an examiner pull a snippet of that email from the notification database, for example.

AmCache.hve
Speaking of Yogesh's comments regarding the AmCache.hve file, one of his posts indicates that it would be a goldmine for malware hunters.  As I mentioned in my previous post on the subject, in the past two months, I've examined two Windows 7 systems that were known to be infected with malware, and while I found references to the malware files in the AppCompatCache, I did not find references to the files in the AmCache.hve file.

To be clear, I'm not saying that either Yogesh's or Eric's comments are incorrect...not at all.  I'm not saying that, suggesting that, or trying to imply that.  What I am saying is that I haven't seen it yet...but also like I said before, that doesn't mean that I'm going to stop looking.

Prefetch
I haven't mentioned Prefetch artifacts in this blog for a while, as I really haven't had any reason to do so.  However, I recently ran across Luis Rocha's Prefetch Artifacts post over on the CountUponSecurity blog, and I found it to be a pretty valuable reference.  

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