Analysis by: Christopher Daniel So
ALIASES:

Net-Worm.Win32.Morto.u (Kaspersky), Mal/Morto-A (Sophos)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This worm may be dropped by other malware.

  TECHNICAL DETAILS

File Size: 8,704 bytes
File Type: DLL
Initial Samples Received Date: 09 Sep 2011

Arrival Details

This worm may be dropped by other malware.

NOTES:

This malware tries to open the file \\TsClient\A\Moto if it is running in rundll32.dll. If successful, it executes the bytes in the file \\TsClient\A\Moto. It then forcefully logs the user off.

If the malware is not executing in rundll32.dll, it reads the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\Wpa
md = "{random values}"

It then executes the returned {random values}.

  SOLUTION

Minimum Scan Engine: 9.200
FIRST VSAPI PATTERN FILE: 8.416.06
FIRST VSAPI PATTERN DATE: 09 Sep 2011

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Scan your computer with your Trend Micro product to delete files detected as WORM_MORTO.SMAI. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


Did this description help? Tell us how we did.