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

Zunker.B is a backdoor that allows hackers to gain remote access to the affected computer in order to carry out actions that compromise user confidentiality and impede the tasks performed on the computer.

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.

• On remote sites: it mass mails junk mail (spam).

Zunker.B 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.
• Peer-to-peer (P2P) file sharing programs: it makes copies of itself with enticing names in shared folders belonging to these programs. Other users of this type of networks then voluntarily download and run the infected files.