Worm.Win32.Ainslot.VB_07211d1428

by malwarelabrobot on January 27th, 2014 in Malware Descriptions.

Gen:Variant.MSILKrypt.6 (BitDefender), Trojan.Win32.Reconyc.fvc (Kaspersky), Gen:Variant.MSILKrypt.6 (B) (Emsisoft), Artemis!07211D142890 (McAfee), Trojan-Downloader (Ikarus), Gen:Variant.MSILKrypt.6 (FSecure), MSIL:Downloader-LD [Trj] (Avast), Backdoor.Win32.PcClient.FD, Worm.Win32.Ainslot.VB.FD, GenericAutorunWorm.YR, WormAinslot_VariantOfZeus.YR (Lavasoft MAS)
Behaviour: Trojan-Downloader, Trojan, Backdoor, Worm, WormAutorun


The description has been automatically generated by Lavasoft Malware Analysis System and it may contain incomplete or inaccurate information.

Summary
Technical Details
Removal Recommendations

MD5: 07211d142890f0f51588a68c1119c822
SHA1: e03832b46f8ec57542f420e2a19cc06f958a1a4e
SHA256: ed17c0ee17f2d3add061775e0d13d6bf3a3f113a27bc3ee78599b1b9495e7279
SSDeep: 3072:m/hCQbkcfQCYRlww1Gni2SSyrsiec280alUE0YtwNHCSZLTcK:mLm6nr7ct8E0uas
Size: 201728 bytes
File type: EXE
Platform: WIN32
Entropy: Packed
PEID: MicrosoftVisualC, NETexecutable, UPolyXv05_v6
Company: no certificate found
Created at: 2013-11-01 17:56:38
Analyzed on: WindowsXP SP3 32-bit


Summary:

Worm. A program that is primarily replicating on networks or removable drives.

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):

rundll32.exe:1520
dumprep.exe:1536
dumprep.exe:1228

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

%original file name%.exe:508

File activity

The process %original file name%.exe:508 makes changes in the file system.
The Worm creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Local Settings\Application Data\XywU7TCHlHV\Njf6X0qm.exe (201 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\xcoca.ine (7547 bytes)

The process dumprep.exe:1536 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\WERadb6.dir00\svchost.exe.mdmp (87325 bytes)

The process dumprep.exe:1228 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\WERadb6.dir00\svchost.exe.hdmp (186817 bytes)

Registry activity

The process %original file name%.exe:508 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "A8 2F 4A CB D4 E9 F3 68 37 24 32 88 B4 05 E4 5A"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"
"Local AppData" = "%Documents and Settings%\%current user%\Local Settings\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]
"Njf6X0qm" = "%Documents and Settings%\%current user%\Local Settings\Application Data\XywU7TCHlHV\Njf6X0qm.exe"

The process rundll32.exe:1520 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "11 62 E7 FE 39 51 84 46 36 3E 62 7A C4 B8 5C 41"

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

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

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

The process dumprep.exe:1536 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "AF 52 CD 8C 50 A8 59 C8 4A 9E 03 4B 75 72 78 4C"

The process dumprep.exe:1228 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "2F 98 36 4E C4 83 58 25 F5 7D 8E 60 1C AF 3D 6B"

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.


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):

    rundll32.exe:1520
    dumprep.exe:1536
    dumprep.exe:1228

  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\Application Data\XywU7TCHlHV\Njf6X0qm.exe (201 bytes)
    %Documents and Settings%\%current user%\Local Settings\Temp\xcoca.ine (7547 bytes)
    %Documents and Settings%\%current user%\Local Settings\Temp\WERadb6.dir00\svchost.exe.mdmp (87325 bytes)
    %Documents and Settings%\%current user%\Local Settings\Temp\WERadb6.dir00\svchost.exe.hdmp (186817 bytes)

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

    [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
    "Njf6X0qm" = "%Documents and Settings%\%current user%\Local Settings\Application Data\XywU7TCHlHV\Njf6X0qm.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.