Worm.Win32.Ainslot.VB_50e6253230

Dynamic Analysis

Payload

Behaviour	Description
WormAutorun	A worm can spread via removable drives. It writes its executable and creates "autorun.inf" scripts on all removable drives. The autorun script will execute the Worm's file once a user opens a drive's folder in Windows Explorer.

Process activity

The Worm creates the following process(es):

Reader_sl.exe:1064
wuauclt.exe:344
50e6253230aac7cf0c7666b1dbc807a7.exe:372
reg.exe:664
reg.exe:1184
reg.exe:620
reg.exe:616
jusched.exe:1056

The Worm injects its code into the following process(es):

vbc.exe:468

File activity

The process wuauclt.exe:344 makes changes in a file system.

The Worm creates and/or writes to the following file(s):

%WinDir%\SoftwareDistribution\DataStore\Logs\edb.chk (100 bytes)
%WinDir%\SoftwareDistribution\DataStore\Logs\edb.log (3576 bytes)
%WinDir%\SoftwareDistribution\DataStore\DataStore.edb (100 bytes)

The Worm deletes the following file(s):

%WinDir%\SoftwareDistribution\DataStore\Logs\tmp.edb (0 bytes)

The process 50e6253230aac7cf0c7666b1dbc807a7.exe:372 makes changes in a file system.

The Worm creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Application Data\Win Update.exe (2105 bytes)

The process vbc.exe:468 makes changes in a file system.

The Worm creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Application Data\FXLKGAH3JJ.exe (3860 bytes)

The process jusched.exe:1056 makes changes in a file system.

The Worm creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Local Settings\Temp\jusched.log (347 bytes)

Registry activity

The process Reader_sl.exe:1064 makes changes in a system registry.

The Worm creates and/or sets the following values in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd73-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd72-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{b98117e8-75ca-11e2-81b2-000c293708fb}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd75-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

The process 50e6253230aac7cf0c7666b1dbc807a7.exe:372 makes changes in a system registry.

The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "56 BE CD 6F 1C 26 73 2A 8B 81 DB 1C 9B A9 A3 C1"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cache" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files"

To automatically run itself each time Windows is booted, the Worm adds the following link to its file to the system registry autorun key:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Win Update" = "%Documents and Settings%\%current user%\Application Data\Win Update.exe"

The process vbc.exe:468 makes changes in a system registry.

The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "4D E9 71 E9 EE DF C7 90 99 F1 5F 4F B4 B8 98 02"

[HKCU\Software\VB and VBA Program Settings\SrvID\ID]
"IZ81UI9DOK" = "bots"

[HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components\{EFECEBAA-170F-DD1E-CD6B-ABDBB8FBD3CA}]
"StubPath" = "%Documents and Settings%\%current user%\Application Data\FXLKGAH3JJ.exe"

[HKCU\Software\VB and VBA Program Settings\INSTALL\DATE]
"IZ81UI9DOK" = "August 11, 2013"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\run]
"windows update" = "%Documents and Settings%\%current user%\Application Data\FXLKGAH3JJ.exe"

[HKCU\Software\Microsoft\Active Setup\Installed Components\{EFECEBAA-170F-DD1E-CD6B-ABDBB8FBD3CA}]
"StubPath" = "%Documents and Settings%\%current user%\Application Data\FXLKGAH3JJ.exe"

To automatically run itself each time Windows is booted, the Worm adds the following link to its file to the system registry autorun key:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"windows update" = "%Documents and Settings%\%current user%\Application Data\FXLKGAH3JJ.exe"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
"windows update" = "%Documents and Settings%\%current user%\Application Data\FXLKGAH3JJ.exe"

The process reg.exe:664 makes changes in a system registry.

The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "F7 F7 BA 8F 11 92 B4 59 81 D9 B1 6D E9 1A 62 8F"

[HKLM\System\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile]
"DoNotAllowExceptions" = "0"

The process reg.exe:1184 makes changes in a system registry.

The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "36 88 FF C0 6F F9 88 DE 6B 44 17 E0 77 10 B4 70"

Adds a rule to the firewall Windows which allows any network activity:

[HKLM\System\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List\%Documents and Settings%\%current user%\Application Data]
"FXLKGAH3JJ.exe" = "%Documents and Settings%\%current user%\Application Data\FXLKGAH3JJ.exe:*:Enabled:Windows Messanger"

The process reg.exe:620 makes changes in a system registry.

The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "2F 41 C3 E8 29 3F 09 D5 AB 8D 7E 50 96 82 B9 BB"

[HKLM\System\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile]
"DoNotAllowExceptions" = "0"

The process reg.exe:616 makes changes in a system registry.

The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "6A 09 28 59 61 8D 13 3F 6C 7B 6F CD 8E 8A F0 E8"

Adds a rule to the firewall Windows which allows any network activity:

[HKLM\System\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List\C:\Windows\Microsoft.NET\Framework\v2.0.50727]
"vbc.exe" = "C:\Windows\Microsoft.NET\Framework\v2.0.50727\vbc.exe:*:Enabled:Windows Messanger"

Network activity (URLs)

No activity has been detected.

Rootkit activity

No anomalies have been detected.

Propagation

A worm can spread via removable drives. It writes its executable and creates "autorun.inf" scripts on all removable drives. The autorun script will execute the Worm's file once a user opens a drive's folder in Windows Explorer.

Removals

Remove it with Ad-Aware

1. Click (here) to download and install Ad-Aware Free Antivirus.
2. Update the definition files.
3. Run a full scan of your computer.

Manual removal*

1. Terminate malicious process(es) (How to End a Process With the Task Manager):

   wuauclt.exe:344
   50e6253230aac7cf0c7666b1dbc807a7.exe:372
   reg.exe:664
   reg.exe:1184
   reg.exe:620
   reg.exe:616
   

2. Delete the original Worm file.
   
3. Delete or disinfect the following files created/modified by the Worm:

   %WinDir%\SoftwareDistribution\DataStore\Logs\edb.chk (100 bytes)
   %WinDir%\SoftwareDistribution\DataStore\Logs\edb.log (3576 bytes)
   %WinDir%\SoftwareDistribution\DataStore\DataStore.edb (100 bytes)
   %Documents and Settings%\%current user%\Application Data\Win Update.exe (2105 bytes)
   %Documents and Settings%\%current user%\Application Data\FXLKGAH3JJ.exe (3860 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\jusched.log (347 bytes)

4. Delete the following value(s) in the autorun key (How to Work with System Registry):

   [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
   "Win Update" = "%Documents and Settings%\%current user%\Application Data\Win Update.exe"
   
   [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
   "windows update" = "%Documents and Settings%\%current user%\Application Data\FXLKGAH3JJ.exe"
   
   [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
   "windows update" = "%Documents and Settings%\%current user%\Application Data\FXLKGAH3JJ.exe"

5. Find and delete all copies of the worm's file together with "autorun.inf" scripts on removable drives.
   
6. Reboot the computer.
   

*Manual removal may cause unexpected system behaviour and should be performed at your own risk.

Static Analysis

Network Activity

Map

Strings from Dumps