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

Mytob.FL is a worm that spreads by copying itself, without infecting other files.

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 opens one or more ports to allow remote access to the computer and takes action that compromises user confidentiality; it awaits remote-control orders received through IRC.

Mytob.FL prevents access from programs to websites of several companies related with security tools (antivirus programs, firewalls, etc.).

Mytob.FL 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.
• Email: sending emails that include a copy of itself as an attachment. The computer is infected when the attachment is run.