Chalking another one up to the "when-will-we-learn category," security software provider Sophos on Tuesday warned that hackers are busily luring users to a malicious site with promises of pornographic pictures.

The company issued an advisory that a widespread spam campaign is tricking users into downloading a spyware Trojan. The e-mails, which lure users with phrases like 'hot photos from my birthday', have fraudulent links to what they say will be online porn, but the links lead to a Web site containing the Troj/Pushu-A Trojan. Once it infects a machine, the malware tries to steal information from the PC.

According to Sophos analysts, visitors to the Web site are encouraged to download what they believe will be a selection of hardcore pornographic photographs in an archive file. The file actually is the malicious executable called xxx.exe or foto.exe. When investigating one Web site hosting the malware, Sophos analysts also discovered a photograph of two American comedians, Lewis Black and Dave Attell, which is apparently unrelated to either the spam e-mails or the malware itself.

"As with all messages offering salacious content, the danger is that some people may be so excited about the prospect of viewing the pictures that they'll click before thinking about what might be in the best interests of their PC's health," said Graham Cluley, senior technology consultant for Sophos, in a written statement. "The comics in the photograph certainly add a strange twist, though it's unlikely anyone will be laughing if their PCs are compromised by downloading Pushu."