Wednesday, April 14, 2010

More Links

RegRipper in Use
Simon posted to the Praetorian Prefect blog recently regarding WinPE. In his post, Simon described installing and using RegRipper from the Windows Forensic Environment (WinFE). Very cool! RegRipper (well, specifically ripXP) was designed for XP System Restore Point analysis, and RegRipper itself has been used via F-Response, and on an analysis system to extract Registry data from mounted Volume Shadow Copies.

F-Response
Speaking of WinFE, Matt posted recently on creating a WinFE bootable CD with F-Response pre-installed! Matt shows you how to use Troy's WinFE instructions to quickly make the installation F-Response ready! Along with the Linux bootable CDs Matt's put together, it looks like he's building out a pretty complete set.

XP Mode Issues
I found this on Securabit, how the installation and use of XP Mode in Windows 7 exposes the system to XP OS vulnerabilities, as well as vulnerabilities to applications run through XP Mode. This is going to be a bit more of an issue, now that MS has removed that hardware virtualization requirement for XP Mode to run, making it accessible to everyone. Core Security Technologies announced a VPC hypervisor memory protection bug...wait, is that bad?

Well, I like to look at this stuff from an IR/DF perspective. Right now, we've got enough issues trying to identify the initial infection vector...now we've got to deal with it in two operating systems! I've installed XP Mode, and during the installation, the XP VM gets these little icons for the C: and D: drives in my host...hey, wait a sec! So XP can "see" my Windows 7? Uh...is that bad?

Installing and using Windows 7 isn't bad in and of itself...it's really no different from when we moved from Windows 2000 to XP. New challenges and issues were introduced, and the IT community, as well as those of us in the IR/DF community learn to cope. In this case, IT admins need to remain even more vigilant because now we're adding old issues in with the new...don't think that we've closed the hole by installing Windows 7, only to be running a legacy app...with it's inherent vulnerabilities...through XP Mode.

Volume Shadow Copies
Found this excellent post over on the Forensics from the Sausage Factory blog, detailing mounting a Volume Shadow Copy with EnCase and using RoboCopy to grab files. Rob Lee has posted on creating timelines from Volume Shadow Copies, and accessing VSCs has been addressed several times (here, and here). With Vista and now Windows 7 systems becoming more pervasive (a friend of mine in LE has already had to deal with a Windows 7 system), accessing Volume Shadow Copies is going to become more and more of an issue...and by that I mean requirement and necessity. So it's good that the information is out there...

MFT Analysis
Rob Lee posted to the SANS Forensic Blog regarding Windows 7 MFT Entry Timestamp Properties. This is a very interesting approach, because there's been some discussion in other forums, including the Win4n6 Yahoo group, around using information from the MFT to create or augment a timeline. For example, using most tools to get file system metadata, you'll get the entries from the $STANDARD_INFORMATION (SIA) attribute, but the information in the $FILE_NAME (FNA) attribute can also be valuable, particularly if the creation dates are different.

When tools are used to alter file time stamps, you'll notice the differences in the SIA and FNA time values, as Lance pointed out. Brian also mentions this like three times in one of the chapters of his File System Forensic Analysis book. So, knowing how various actions can affect file system time stamps can be extremely important to creating or adding context to a timeline, as well as to the overall analysis.

The Future
Rob's efforts in this area got me to thinking...how long will it be before forensic analysts sit down at their workstation to being analysis, and have a Kindle or an iPad or similar device right there with them, to assist them with their analysis workflow? Given the complexity and variety of devices and operating systems, it would stand to reason that an organization would have a workflow with supporting information (docs like what Rob's putting together, etc.), possibly even online in one location. The analyst would access the online (internally, of course) app and enter their information and begin their case, and they would be presented with workflow, processes and supporting information. In fact, something like that could also provide for case management, as well as case notes and collaboration, and even ease reporting.

Is the workflow important? I'd suggest that yes, it is...wholeheartedly. I've seen a number of folks stumble over what they were looking for and spend a lot of time doing things that really didn't get them any closer to their goals...if they had and understood their goals! This would not obviate the need for training, of course, particularly in basic skills, but having some kind of Wiki-ish framework with a workflow template for an analyst to follow would definitely be beneficial...that is, aside from its CSI coolness (I still yell, "Lt Dan!" at the TV whenever Gary Sinise comes on screen in CSI:NY).

3 comments:

Bugbear said...

In regards to $MFT Dates. Recently posted the results of some experimenting I did with PowerShell and renaming a file post system time change. Indeed this will change the FNA Dates (with the exception of the FNA MFT Modified Date which certainly would be a red flag). My post can be found here:

http://securitybraindump.blogspot.com/2010/04/tampering-with-master-file-table.html

Keep up the great posts! I am learning a ton.

Thanks

Tim
@bug_bear

rwuiuc said...

I agree with the work flow perspective.. building a framework for the case at the beginning and having it flexible enough to adapt to the facts for each case would be great. I have been playing with a couple of different tools to try and do that. Rough stuff but things like a customized tiddlywiki for each case or taskcoach portable.

I like these portable apps because I can create a standard template and then script out a case structure for each case to plan, track, and document my work on each case.

Keydet89 said...

Good idea with the portable tools...even having a checklist works. I've done it such that a senior member works with whomever is doing the analysis to develop an analysis plan before the actual analysis begins. This ensures that there are understandable, achievable goals in place, and still provides for flexibility.