WORM_DASHER.A

November 28, 2012
 Analysis by: Anthony Joe Melgarejo
 ALIASES:

Worm:Win32/Dasher.A (Microsoft), W32.Dasher.A (Symantec), W32/Dasher.worm.gen (McAfee)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

  TECHNICAL DETAILS

File Size:

7,680 bytes

Memory Resident:

Yes

Initial Samples Received Date:

08 Apr 2009

Arrival Details

This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This worm drops the following files:

  • %Temp%\log.txt
  • %Current%\Result.txt
  • %Current%\SqlScan.bat
  • %Current%\Temp.txt

(Note: %Temp% is the Windows Temporary folder, which is usually C:\Windows\Temp.)

Autostart Technique

This worm adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\Microsoft\Windows\
CurrentVersion\Run
Windows Update = "%Current%\{malware file name}.exe"