Security vendor McAfee has claimed that they have detected in wild a Trojan Horse, which pretends to be a Mozilla Firefox extension.

They have named this Trojan “FormSpy”. Trojans are basically programs, which appear to be harmless but can be quite damaging to user privacy.

The company added that this Trojan is downloaded on a machine, which is already infected with another Trojan horse called “Downloader-AXM”.

This Downloader-AXM contacts server to download other malicious programs to a computer without letting the user know about it.

And once this new Trojan is downloaded, it installs itself as a Firefox extension and monitor user’s activity on the net. It pretends to be the “NumberedLinks 0.9″ extension and in reality transmit information in a Web browser to another Web site.

McAfee added that this Trojan is also capable of stealing e-mail, ICQ instant messaging service, and FTP passwords.