Although it was first only a rumor, it's official this time: the Avast forum was hacked and some dangerous files were attached in order to install malware on visitors' computers. It appears that some of the antiviruses detected the problem but some of the unprotected users may have their computers infected. A post on the AnandTech forum reported the problem, the user nicknamed "lusher" being among the first ones who discovered the glitch. It appears that NOD32 and F-Prot identified the malware but it's not yet confirmed if Avast managed to protect its users against the forum threat.

"The AVAST forum was hacked and an iframe was inserted to some malicious site that was using a security exploit to install malware! They pulled the forum offline now, but I was nearly hit, when I visited the forum yesteday, I got a message from my antivirus, I thought it was a FP , but just quarantined it anyway and thought nothing of it and then continued on my way. But I guess I was wrong!" lusher wrote on the AnandTech forum.

"I guess you must never let your guard down, even in 'trusted' sites. If you can't trust antivirus sites, who can you trust? Oh yeah they pulled the forum down now. But it was on there for at least 24 hours..."

At this time, the forum is up and running and it seems like the Internet Explorer users are the only ones affected by the malware. Obviously, the IE engine based browsers are also affected. Firefox and Opera clients were not in danger, another forum post on the Avast website stated.

"Basically something hacked the forum Simple Machines PHP software injecting an iframe tag in to each page as it was loaded, that page tried to infect users with the storm worm. Those with Firefox or Opera weren't vulnerable but those with IE or a clone were vulnerable to attack, however the web shield blocked that attack," DavidR wrote on the Avast forum.