Saturday, February 21, 2009

VMWare Running? Better Check for Different Windows Operating System's EPROCESS Blocks

Identify Multiple Windows OS Versions in a Single RAM Capture if the Host Machine is Running VMWare Machines.

I often run VMWare Machines, on my host machine,so I can easily grab the machine's RAM contents by suspending the machine and analyzing the VMEM file. Nothing new there. But what is cool is when you run several VMWare machines (or just one) and grab the RAM of the host machine. If you use other tools to determine which OS is running they will only identify what OS is running on the “Host” machine and not what OS(s) are being running on VMWare machines.

So to find out which different Windows OSs were running in your captured RAM use the following GREP search across your RAM acquisition
\x4E\x00\x54\x00\x20\x00\x4B\x00\x65\x00\x72\x00\x6E\x00\x65\x00\x6C\x00\x20\x00\x26\x00\x20\x00\x53\x00\x79\x00\x73\x00\x74\x00\x65\x00\x6D\x00\x00\x00\x00\x00[\x00-\xFF]\x00[\x00-\xFF]\x00\x01\x00\x46\x00\x69\x00\x6C\x00\x65\x00\x56\x00\x65\x00\x72\x00\x73\x00\x69\x00\x6F\x00\x6E\x00\x00\x00\x00\x00

The GREP expression loosely translates to,
“N.T. .K.e.r.n.e.l. .&. .S.y.s.t.e.m........... F.i.l.e.V.e.r.s.i.o.n.....”.

This is the same GREP Expression in the RAM Enscript I created. (In the enscript the” \” is “\\”). The GREP expression is the magic number needed to find the metadata contained in the NTOSKRNL.exe. The following bytes after this GREP is the Windows OS File Version Number The file version can then be converted to the Specific Windows OS. The following is an example from the RAM Acquistion with the HOST OS (WinXPSP2) and Two VMWARE Machines (Vista and Win200) ________________________________________
Comment Operating System: Windows XPSP2 Internal Version Number = 5.1.2
File Offset 7209948
N·T· ·K·e·r·n·e·l· ·&· ·S·y·s·t·e·m·····r·)···F·i·l·e·V·e·r·s·i·o·n·····
________________________________________
Comment Operating System: Windows Vista Internal Version Number = 6.0.6
File Offset 445911836
N·T· ·K·e·r·n·e·l· ·&· ·S·y·s·t·e·m·····n·'···F·i·l·e·V·e·r·s·i·o·n·····
________________________________________
Comment Operating System: Windows 2000 Internal Version Number = 5.00.
File Offset 712069132
N·T· ·K·e·r·n·e·l· ·&· ·S·y·s·t·e·m·····8·····F·i·l·e·V·e·r·s·i·o·n·····
________________________________________

During my testing I also shutdown the VMWare Machines for approximately 10 minutes and re-acquired the RAM. I still found the OS Metadata, of one of the Machines in the second RAM acquisition. Showing there is some persistence of VMWARE' Machine's RAM in the HOST Memory. (No additional programs were started by the user during the ten minute waiting period-except the RAM acquisition tool).

Once you have the different OSs inside your RAM you can also use the same RAM Enscript to find the running/exited processes (EPROCESS Blocks) of each OS along with the other remnants. The Second RAM Acquisition did not contain the OS Metadata for the Vista VM but I still found 20 unique Vista EPROCESS Blocks. I also found about 7 unique EPROCESS Blocks from he Win2000 VM. Showing a little persistence in the RAM

So yeah... this is cool in the lab... but not sure how often anyone will need this information in the “Real World”.

Thanks to Eric at Digital Intelligence for idea of checking for this...

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