Worm.Win32.Ainslot.VB_a1c3d9964a

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):

csc.exe:1760
cvtres.exe:1484
rundll32.exe:1068
reg.exe:1608
reg.exe:1456
reg.exe:864
reg.exe:1680
dumprep.exe:1820
dumprep.exe:1556

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

%original file name%.exe:1268

File activity

The process csc.exe:1760 makes changes in the file system.

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

%Documents and Settings%\%current user%\Local Settings\Temp\CSC1.tmp (652 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.out (396 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.dll (3218 bytes)

The Worm deletes the following file(s):

%Documents and Settings%\%current user%\Local Settings\Temp\CSC1.tmp (0 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\RES2.tmp (0 bytes)

The process %original file name%.exe:1268 makes changes in the file system.

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

%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.cmdline (227 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\AppLaunch\App.ine (7547 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.0.cs (1 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.out (294 bytes)
%Documents and Settings%\%current user%\Application Data\tmp74.exe (4185 bytes)
%Documents and Settings%\%current user%\Application Data\tmp75.exe (4185 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\Tmp420 (18 bytes)

The Worm deletes the following file(s):

%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.cmdline (0 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.0.cs (0 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.out (0 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.dll (0 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.tmp (0 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.err (0 bytes)

The process cvtres.exe:1484 makes changes in the file system.

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

%Documents and Settings%\%current user%\Local Settings\Temp\RES2.tmp (2912 bytes)

The process dumprep.exe:1820 makes changes in the file system.

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

%Documents and Settings%\%current user%\Local Settings\Temp\WERb6df.dir00\svchost.exe.hdmp (224604 bytes)

The process dumprep.exe:1556 makes changes in the file system.

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

%Documents and Settings%\%current user%\Local Settings\Temp\WERb6df.dir00\svchost.exe.mdmp (100055 bytes)

Registry activity

The process csc.exe:1760 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "1A 91 16 15 43 2B 54 39 66 AF CA B8 4F 34 A7 AC"

The process %original file name%.exe:1268 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "90 C4 67 82 DC E1 72 80 A8 D4 A1 13 7E D5 63 89"

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

"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]
"FacbookUpdate" = "c:\%original file name%.exe"

The process cvtres.exe:1484 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "C2 8D A0 6B 9D C2 19 D5 B0 E5 C1 7B 36 FC D5 EC"

The process rundll32.exe:1068 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "0C 7D 39 BC CB 48 3C 50 CA DD 6D 84 51 65 AE 65"

[HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Layers\%Documents and Settings%\%current user%\Local Settings\Temp\AppLaunch]
"svchost.exe" = "EnableNXShowUI"

[HKCU\Software\Microsoft\Windows\ShellNoRoam\MUICache\%Documents and Settings%\%current user%\Local Settings\Temp\AppLaunch]
"svchost.exe" = "Visual Basic Command Line Compiler"

[HKLM\System\CurrentControlSet\Control\Session Manager\AppCompatibility]
"AppCompatCache" = "EF BE AD DE 60 00 00 00 00 00 00 00 00 00 00 00"

The process reg.exe:1608 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "AA FC 05 DC 71 F5 94 76 9E 20 9C D9 B6 33 67 AC"

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

The process reg.exe:1456 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "C2 1F 24 C9 EC 58 C6 45 D4 3E D2 FA 71 FE 2F CD"

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%\Local Settings\Temp\AppLaunch]
"svchost.exe" = "%Documents and Settings%\%current user%\Local Settings\Temp\AppLaunch\svchost.exe:*:Enabled:Windows Messanger"

The process reg.exe:864 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "7A 88 9B ED 97 95 49 C2 03 40 70 0B E1 87 B7 8C"

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

[HKLM\System\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List\C:\DOCUME~1\"%CurrentUserName%"\LOCALS~1\Temp]
"WinKllefender.exe" = "C:\DOCUME~1\"%CurrentUserName%"\LOCALS~1\Temp\WinKllefender.exe:*:Enabled:Windows Messanger"

The process reg.exe:1680 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "17 98 6D 3E D7 1A 16 14 DE 70 F5 1B CB A8 E5 11"

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

The process dumprep.exe:1820 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "6D 20 EF F9 B0 FE 11 7C 74 C8 6A CA 48 14 EB 60"

The process dumprep.exe:1556 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "32 69 0F 94 5A 23 70 BB A8 F2 E2 1E 11 FF 01 A2"

Network activity (URLs)

No activity has been detected.

HOSTS file anomalies

No changes have 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):

   csc.exe:1760
   cvtres.exe:1484
   rundll32.exe:1068
   reg.exe:1608
   reg.exe:1456
   reg.exe:864
   reg.exe:1680
   dumprep.exe:1820
   dumprep.exe:1556

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

   %Documents and Settings%\%current user%\Local Settings\Temp\CSC1.tmp (652 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.out (396 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.dll (3218 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.cmdline (227 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\AppLaunch\App.ine (7547 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\bkjuz_wm.0.cs (1 bytes)
   %Documents and Settings%\%current user%\Application Data\tmp74.exe (4185 bytes)
   %Documents and Settings%\%current user%\Application Data\tmp75.exe (4185 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\Tmp420 (18 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\RES2.tmp (2912 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\WERb6df.dir00\svchost.exe.hdmp (224604 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\WERb6df.dir00\svchost.exe.mdmp (100055 bytes)

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

   [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
   "FacbookUpdate" = "c:\%original file name%.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