According to security experts, poisoned links on social networks are a big problem. In an , researchers set up accounts on 11 social networks and found that not one of those networks stopped them from posting malware links. In addition, nine of the 11 links failed to block links listed in a Google compilation of poisoned websites.

"The social networks we tested have some work to do on their malware countermeasures," says Neil Daswani, Dasient CTO.

According to Carole Theriault, a senior consultant at security firm Sophos, "Facebook is a very enticing playground for bad guys. It is no surprise that surveys have shown an increase in malware activity on the site."

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