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  3. W32.Sober.X@mm


Risk Level 3: Moderate

November 19, 2005
February 13, 2007 12:46:35 PM
Also Known As:
CME-681, WORM_SOBER.AG [Trend Micro], W32/Sober-{X, Z} [Sophos], Win32.Sober.W [Computer Associ, Sober.Y [F-Secure], W32/Sober@MM!M681 [McAfee], W32/Sober.AA@mm [Norman], Win32/Sober.Z@mm [Microsoft]
Systems Affected:
Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows XP

W32.Sober.X@mm is a mass-mailing worm that uses its own SMTP engine to spread and lowers security settings. It sends itself as an email attachment to addresses gathered from the compromised computer. The email may be in either English or German.

Note: Symantec products that support the Worm Blocking functionality automatically detect this threat as it attempts to spread.

Antivirus Protection Dates

  • Initial Rapid Release version November 19, 2005
  • Latest Rapid Release version June 24, 2014 revision 006
  • Initial Daily Certified version November 19, 2005
  • Latest Daily Certified version September 12, 2012 revision 004
  • Initial Weekly Certified release date November 22, 2005
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Threat Assessment


  • Wild Level: Medium
  • Number of Infections: More than 1000
  • Number of Sites: More than 10
  • Geographical Distribution: Low
  • Threat Containment: Easy
  • Removal: Moderate


  • Damage Level: Medium


  • Distribution Level: High
Writeup By: Takayoshi Nakayama

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