W32.Gaobot.UL

W32.Gaobot.UL is a variant of W32.HLLW.Gaobot.gen. It attempts to spread through network shares that have weak passwords and allows attackers to access an infected computer through a predetermined IRC channel.

The worm uses multiple vulnerabilities to spread, including:

• The DCOM RPC vulnerability (described in Microsoft Security Bulletin MS03-026) using TCP port 135.
• The RPC locator vulnerability (described in Microsoft Security Bulletin MS03-001) using TCP port 445.
• The WebDav vulnerability (described in Microsoft Security Bulletin MS03-007) using TCP port 80.
• The Workstation service buffer overrun vulnerability (described in Microsoft Security Bulletin MS03-049) using TCP port 445.

W32.Gaobot.UL is packed with PE Diminisher.

Protection

• Initial Rapid Release version April 1, 2004
• Latest Rapid Release version August 20, 2008 revision 017
• Initial Daily Certified version April 1, 2004
• Latest Daily Certified version January 20, 2009 revision 048
• Initial Weekly Certified release date April 1, 2004

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: Moderate
• Removal: Difficult

Damage

• Damage Level: Medium

Distribution

• Distribution Level: Medium