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Showing posts with label vss. Show all posts
Showing posts with label vss. Show all posts
vss

Daily Blog #354: Determining the number of active shadow volumes copies from an unmounted image

Determining the number of active shadow volumes copies from an unmounted image

Hello Reader,
        Sometimes you just need to know before you go through the process of load all of the you ant to know if there are any volume shadow copies and from what dates. When searching for more information one event log entries related to VSS I found a paper written up by some Champlain students:

http://www.champlain.edu/Documents/LCDI/archive/Volume-shadow-Report_Redux.pdf

Which made reference to the following path:
\System Volume Information\SPP\OnlineMetadataCache

I loaded up FTK Imager and quickly inspected two systems I have to see what I would find there. The first system has Volume Shadow Copies turned on and within the directory I found a file that began with a GUID that matched the Shadow GUID returned by VSS admin and a modification date that matched the date that the shadow copy was made. This was very handy as I can now have a quick way to validate if the shadow copies my forensic tools are exposing to me are valid without having to rely on VSSAdmin.

The second system was more interesting to me. When I first started using the system I turned off volume shadow copies, I hated that it would create a snapshot every time I installed software, and VSSAdmin shows there are no active shadow files. What I found in the OnlineMetadataCache directory surprised me. Contained within it where the original volume shadow metadata catalogs from when my system did have VSCs turned on, turning off the VSC functionality never removed them.

So take aways:
1. If you want to know the last VSC made before VSCs were turned off, check the OnlineMetadataCache directory.

2. If you want to validate that the VSCs you see in your forensic tool line up with what the OS is storing, check the OnlineMetadataCache directory.

3. If you want to validate what caused a VSC to be deleted, look for deleted files in the OnlineMetadataCache directory (both in the MFT and Journals) and then look for Event 33 to see if the deletion was done by the system or by the user.

vss

Daily Blog #353: Volume Shadow deletion event IDs

Volume Shadow deletion event IDs by David Cowen - Hacking Exposed Computer Forensics Blog


Hello Reader,
          Ever look at a image that had Volume Shadow Copies and wonder if the volume shadow copies were deleted by the system or turned off by the user? In that case check out Event ID 33 in the System log and the source of volsnap. You'll see a message similar to this:
The oldest shadow copy of volume C: was deleted to keep disk space usage for shadow copies of volume C: below the user defined limit.

Here is a screenshot below showing the event in Event Viewer:

Volume Shadow deletion event IDs by David Cowen - Hacking Exposed Computer Forensics Blog  
You'll see this for each volume shadow copy that was deleted by the system with a timestamp of when it occurred. On my personal system this goes back a year.

Also Read: Daily Blog #352

vss

Daily Blog #240: Arsenal Image Mounter and Shadowkit

Arsenal Image Mounter and Shadowkit

Hello Reader,
            Often times I'm on a system that I want to access volume shadows on and it runs Windows and I haven't compiled libvshadow on it. So I switch over to the next best thing, Shadowkit and Arsenal Image Mounter.

If you haven't used Arsenal Image Mounter its pretty great, first its free to use. You can download it here: http://arsenalrecon.com/apps/image-mounter/ Second it mounts the images as iSCSI devices which means Windows will see them as locally attached physical disks. It supports raw, multipart raw, s01 and e01 images so its really useful.

Second I grab the latest version of Shadow Kit to pull in the volume shadows and then start exporting the data I need. I like Shadow Kit not only because David Dym who works in our lab wrote it but also because it will exclude all my local shadows and just show me the shadows for the images I have connected identified by hostname. This is very useful and allows me to quickly go through pulling out the data I need. You can grab shadowkit here :

http://www.easymetadata.com/wp/?page_id=63

Now this method isn't perfect, it won't get you access to all the hidden system files as Shadow kit uses the Windows API, but when you need access to underlying shadow data without a lot of time and compilation it does the job!

Also Read: Daily Blog #239