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  3. W32.Gaobot.AFJ


Risk Level 2: Low

April 27, 2004
February 13, 2007 12:22:15 PM
Also Known As:
Backdoor.Agobot.gen [Kaspersky, WORM_AGOBOT.JF [Trend], WORM_AGOBOT.JO [Trend]
Systems Affected:
Windows 2000, Windows NT, Windows XP

W32.Gaobot.AFJ is a worm that spreads through open network shares, backdoors that the Beagle and Mydoom worms install, and several Windows vulnerabilities, including:
The worm can also act as a backdoor server program and attack other systems. Additionally, the worm attempts to stop the process of many antivirus and security programs.

A variant discovered on May 12, 2004 attempts to spread using W32.Sasser.Worm. It does this by injecting code into the "avserve.exe" process, so that when the Sasser worm attempts to propagate, it sends Gaobot to the remote system instead of Sasser. This variant creates a file named "wormride.dll" in the System directory.

Antivirus Protection Dates

  • Initial Rapid Release version April 28, 2004
  • Latest Rapid Release version January 8, 2015 revision 048
  • Initial Daily Certified version April 28, 2004
  • Latest Daily Certified version January 10, 2015 revision 001
  • Initial Weekly Certified release date April 28, 2004
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Threat Assessment


  • Wild Level: Low
  • Number of Infections: 50 - 999
  • Number of Sites: More than 10
  • Geographical Distribution: Low
  • Threat Containment: Easy
  • Removal: Moderate


  • Damage Level: Medium


  • Distribution Level: Medium
Note: On May 14, 2015, modifications will be made to the threat write-ups to streamline the content. The Threat Assessment section will no longer be published as this section is no longer relevant to today's threat landscape. The Risk Level will continue to be the main threat risk assessment indicator.
Writeup By: Kaoru Hayashi

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