Saturday, April 30, 2011

Volatility 1.4 UserAssist plugin

From a computer forensics standpoint, userassist keys can provide a lot of information about user activity (see the Harlan's posts for more information).

After looking at Didier Steven's article on userassist keys for Windows 7 from Into the Boxes issue 0x0 and RegRipper, I decided to write up a plugin that would pull out UserAssist keys from all versions of windows for Volatility.

One thing I decided to add was an enumeration of GUIDs to human friendly folder names, which were obtained from here.

The plugin is available in my git repository. Simply download and place into your volatility/plugins directory and you're set.

Update: This plugin is now part of the core Volatility code

Example Output

Below you can see some snippets of output for Windows 7. The fields are pretty self explanatory, though you can read Didier Steven's article for more details. The hex dump is the actual data from which this information was parsed, just so you can verify it yourself.


$ ./vol.py -f win7.vmem --profile=Win7SP0x86 userassist --no-cache
Volatile Systems Volatility Framework 1.4_rc1
----------------------------
Registry: \??\C:\Users\admin\ntuser.dat
Key name: Count
Last updated: 2010-07-06 22:40:25

Subkeys:

Values:
REG_BINARY Microsoft.Windows.GettingStarted :
Count: 14
Focus Count: 21
Time Focused: 0:07:00.500000
Last updated: 2010-03-09 19:49:20

0000 00 00 00 00 0E 00 00 00 15 00 00 00 A0 68 06 00 .............h..
0010 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0020 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0030 00 00 80 BF 00 00 80 BF FF FF FF FF EC FE 7B 9C ..............{.
0040 C1 BF CA 01 00 00 00 00 ........

REG_BINARY UEME_CTLSESSION :
Count: 187
Focus Count: 1205
Time Focused: 6:25:06.216000
Last updated: 1970-01-01 00:00:00

0000 00 00 00 00 BB 00 00 00 B5 04 00 00 B4 90 60 01 ..............`.
0010 10 00 00 00 39 00 00 00 E9 67 28 00 7B 00 44 00 ....9....g(.{.D.
0020 36 00 35 00 32 00 33 00 31 00 42 00 30 00 2D 00 6.5.2.3.1.B.0.-.
0030 42 00 32 00 46 00 31 00 2D 00 34 00 38 00 35 00 B.2.F.1.-.4.8.5.

[snip]

REG_BINARY %windir%\system32\displayswitch.exe :
Count: 13
Focus Count: 19
Time Focused: 0:06:20.500000
Last updated: 2010-03-09 19:49:20

0000 00 00 00 00 0D 00 00 00 13 00 00 00 60 CC 05 00 ............`...
0010 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0020 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0030 00 00 80 BF 00 00 80 BF FF FF FF FF EC FE 7B 9C ..............{.
0040 C1 BF CA 01 00 00 00 00 ........

REG_BINARY %windir%\system32\calc.exe :
Count: 12
Focus Count: 17
Time Focused: 0:05:40.500000
Last updated: 2010-03-09 19:49:20

0000 00 00 00 00 0C 00 00 00 11 00 00 00 20 30 05 00 ............ 0..
0010 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0020 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0030 00 00 80 BF 00 00 80 BF FF FF FF FF EC FE 7B 9C ..............{.
0040 C1 BF CA 01 00 00 00 00 ........
........

REG_BINARY Z:\vmware-share\apps\odbg110\OLLYDBG.EXE :
Count: 11
Focus Count: 266
Time Focused: 1:19:58.045000
Last updated: 2010-03-18 01:56:31

0000 00 00 00 00 0B 00 00 00 0A 01 00 00 69 34 49 00 ............i4I.
0010 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0020 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0030 00 00 80 BF 00 00 80 BF FF FF FF FF 70 3B CB 3A ............p;.:
0040 3E C6 CA 01 00 00 00 00 >.......

REG_BINARY %ProgramFiles%\Microsoft SDKs\Windows\v7.0\Bin\vsstools\vshadow.exe :
Count: 0
Focus Count: 67
Time Focused: 0:06:12.811000
Last updated: 1970-01-01 00:00:00

0000 00 00 00 00 00 00 00 00 43 00 00 00 57 AE 05 00 ........C...W...
0010 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0020 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0030 00 00 80 BF 00 00 80 BF FF FF FF FF 00 00 00 00 ................
0040 00 00 00 00 00 00 00 00 ........

REG_BINARY %windir%\regedit.exe :
Count: 2
Focus Count: 8
Time Focused: 0:03:22.626000
Last updated: 2010-03-17 23:40:36

0000 00 00 00 00 02 00 00 00 08 00 00 00 8E 15 03 00 ................
0010 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0020 00 00 80 BF 00 00 80 BF 00 00 80 BF 00 00 80 BF ................
0030 00 00 80 BF 00 00 80 BF FF FF FF FF 90 3A 93 3E .............:.>
0040 2B C6 CA 01 00 00 00 00 +.......



Here you can see an example of output from Windows XP:


$ ./vol.py -f XPSP3.vmem --profile=WinXPSP3x86 userassist --no-cache
Volatile Systems Volatility Framework 1.4_rc1
----------------------------
Registry: \Device\HarddiskVolume1\Documents and Settings\Administrator\NTUSER.DAT
Key name: Count
Last updated: 2010-11-24 16:35:34

Subkeys:

Values:
REG_BINARY UEME_CTLSESSION :
0000 91 52 5B 0E 1F 00 00 00 .R[.....

REG_BINARY UEME_CTLCUACount:ctor :
ID: 1
Count: 2
Last updated: 1970-01-01 00:00:00

0000 01 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 ................

REG_BINARY UEME_RUNPATH :
ID: 31
Count: 589
Last updated: 2010-11-24 16:30:49

0000 1F 00 00 00 52 02 00 00 A0 91 09 F4 F4 8B CB 01 ....R...........

REG_BINARY UEME_RUNPATH:D:\SETUP.EXE :
ID: 30
Count: 6
Last updated: 2010-09-20 15:02:47

0000 1E 00 00 00 0B 00 00 00 E0 85 39 E3 D4 58 CB 01 ..........9..X..

REG_BINARY UEME_RUNPIDL :
ID: 31
Count: 124
Last updated: 2010-11-24 14:19:29

0000 1F 00 00 00 81 00 00 00 50 78 79 9B E2 8B CB 01 ........Pxy.....

REG_BINARY UEME_RUNPIDL:%csidl2%\Microsoft Visual Basic 6.0 :
ID: 1
Count: 2
Last updated: 2009-05-12 02:28:10

0000 01 00 00 00 02 00 00 00 B0 1E DB 4A A9 D2 C9 01 ...........J....

REG_BINARY UEME_RUNPATH:C:\Program Files\Microsoft Visual Studio\VB98\VB6.EXE :
ID: 1
Count: 1
Last updated: 2009-05-12 02:28:10

0000 01 00 00 00 06 00 00 00 50 62 FC 4A A9 D2 C9 01 ........Pb.J....

REG_BINARY UEME_RUNPIDL:C:\Documents and Settings\All Users\Start Menu\Windows Update.lnk :
ID: 1
Count: 1
Last updated: 2009-05-12 02:28:36

0000 01 00 00 00 06 00 00 00 F0 D0 A1 5A A9 D2 C9 01 ...........Z....

REG_BINARY UEME_RUNPATH:C:\WINDOWS\system32\wupdmgr.exe :
ID: 31
Count: 2
Last updated: 2010-11-24 14:50:05




Shoutz to ikelos for helping me optimize this :-)


References:

Into the Boxes issue 0x0 http://intotheboxes.wordpress.com/2010/01/01/into-the-boxes-issue-0x0/

RegRipper http://regripper.wordpress.com/

2 comments:

Chad Tilbury said...

Can I be the first to comment on how awesome this plugin is? Userassist is a complicated registry key. The output is wonderfully formatted and the support for XP and Win7 is flawless. Given the major changes that occurred to this key in Win7, I am impressed that the plugin supports both versions. Auto-parsing the GUIDs is a nice touch. Thank you so much for your contributions!

JL said...

Thanks for the comment, Chad! I'm glad that you like it and that you find it useful.

I appreciate the feedback :-)