Spammers have found a fertile new marketplace on social networking sites such as Facebook and MySpace.

The 'wall' feature on Facebook is being abused by spammers to post deceptive messages, linking to spam sites such as online "pharmacy" shops. The tactic is similar to the long-standing link-spamming approach which involves posting misleading links to spamvertised sites on blogs and forums.

Facebook wall spamming is a recent variant on the theme. Spammers are using genuine users’ profiles to disseminate these messages and are buying or ‘renting’ these identities from online thieves, according to preliminary research by security appliance firm Fortinet.

It reckons miscreants obtained access to users' accounts using phishing attacks, deceptive messages that attempt to trick users into handing over their login credentials to hackers. A phishing worm was spotted spreading on Facebook earlier this year and both incidents may be related.

Fortinet has published an advisory on the attack (containing screenshots) here.

Such spam 2.0 lures are a relatively new phenomenon on Facebook, but they've been kicking around on MySpace for much longer.

Spambots on MySpam have recently begun using more sophisticated techniques, net security firm Websense reports. Malformed profiles are created in such a way that they hide all of the real MySpace profile areas. Surfers clicking on these expecting to view pictures or messages are instead met with content from spamvertised sites or worse.

"This technique can easily be adapted for malicious purposes, such as drive-by installers, MySpace phishing, and so forth," Websense researcher Ali Mesdaq warns.

"MySpace has a built-in security feature to catch form submissions to other sites. However, it seems to be reliant on a 'Submit' button being present to trigger the form. Having the warning there is a good, proactive security measure, but if the warning is bypassed, then it does no good." ®

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