World's first inter-protocol exploit, but not the last

Underscoring a little-known web vulnerability, hackers are exploiting a weakness in the Mozilla Firefox browser to wreak havoc on Freenode and other networks that cater to users of internet relay chat.

Using a piece of javascript embedded into a web link, the hackers force users of the open-source browser to join IRC networks and flood channels with diatribes that include the same internet address. As IRC users with Firefox follow the link, their browsers are also forced to spam the channels, giving the attack a viral quality that has has caused major disruptions for almost a month.

"Huge numbers of users of the Freenode network ended up getting banned themselves because they would click the link and then they would join the network and flood the network," one of the hackers, who goes by the moniker Weev, told The Register. "We get this huge rollover effect."

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