Windows 2003/XP/2000/NT/ME/98/95/3.X

Gaobot.QKZ is a worm that spreads by copying itself, without infecting other files.

It captures certain information entered or saved by the user, with the corresponding threat to privacy: passwords saved by certain Windows services; email addresses; user's browsing habits; screenshots of actions carried out.

It affects productivity, preventing tasks from being carried out:

• In the affected computer: it converts the computer into a platform for taking malicious action surreptitiously: spam sending, launch of Denial of Service attacks, malware distribution, etc.

It reduces the security level of the computer: it awaits remote-control orders received through FTP.

It uses stealth techniques to avoid being detected by the user:

• It deletes the original file from which it was run once it is installed on the computer.

It uses several methods in order to avoid detection by antivirus companies:

• It terminates its own execution if it detects that it is being executed in a virtual machine environment, such as VMWare or VirtualPC.

Gaobot.QKZ uses the following propagation or distribution methods:

• Exploiting vulnerabilities with the intervention of the user: exploiting vulnerabilities in file formats or applications. To exploit them successfully it needs the intervention of the user: opening files, viewing malicious web pages, reading emails, etc.
• Via Internet, exploiting remote vulnerabilities: attacking random IP addresses, in which it tries to insert a copy of itself by exploiting one or more vulnerabilities.
• IRC: It sends a copy of itself to all users connected to the channel to which the infected user is connected.
• Instant messaging: it sends links pointing to a copy of itself to all users included in the infected user's contacts list.