Windows 2003/XP/2000/NT/ME/98/95

W32/BotNet.K is a virus that spreads to other computers by copying its code to other files or programs.

It reduces the security level of the computer: it notifies the attacker that the computer has been compromised and is ready to be used maliciously; it listens on open ports in order to control the computer remotely; it awaits remote-control orders received through IRC; it changes system permissions, decreasing the security level.

W32/BotNet.K 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.
• File infection: it infects different types of files, which are then distributed through any of the usual means: floppy disks, email messages with attachments, Internet download, files transferred via FTP, IRC channels, P2P file sharing networks, etc.

W32/BotNet.K uses the following infection strategies:

• Resident: once it has been run, the virus goes memory resident and stops functions belonging to the operating system. Therefore, every time the operating system or an application tries to access any of these functions, the virus will activate and infect new files.
• Prepending: it enters its code at the beginning of the file it infects. By doing this, it ensures that the virus is run every time the infected file is executed, but without interfering the functioning of the file.
• Direct action: it infects a specific number of executable files every time the virus activates, without going memory resident.