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  3. Trojan.Zeroaccess.B

Trojan.Zeroaccess.B

Risk Level 1: Very Low

Discovered:
December 22, 2011
Updated:
November 9, 2012 3:15:51 PM
Type:
Trojan
Infection Length:
Varies
Systems Affected:
Windows 2000, Windows 7, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows Server 2008, Windows Vista, Windows XP
Trojan.Zeroaccess.B is a Trojan horse that uses an advanced rootkit to hide itself. It can also create a hidden file system, download more malware, and open a back door on the compromised computer.

Note: The behavior of this threat on 32-bit computers is almost identical to Trojan.Zeroaccess.

For more information, please see the following resource:
Trojan.Zeroaccess

Antivirus Protection Dates

  • Initial Rapid Release version December 22, 2011 revision 025
  • Latest Rapid Release version June 24, 2014 revision 006
  • Initial Daily Certified version December 22, 2011 revision 032
  • Latest Daily Certified version July 2, 2013 revision 016
  • Initial Weekly Certified release date December 28, 2011
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Threat Assessment

Wild

  • Wild Level: Low
  • Number of Infections: 0 - 49
  • Number of Sites: 0 - 2
  • Geographical Distribution: Low
  • Threat Containment: Easy
  • Removal: Difficult

Damage

  • Damage Level: Medium
  • Payload: Opens a back door.
    Downloads more malware.

Distribution

  • Distribution Level: Low
Writeup By: Karthik Selvaraj and Rong Zhou

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