Mibbit, an irc client within a browser can rotate, is cracked. Hackers probably have user names and passwords of tens of thousands of irc users captured. A hackersgroepering the attack listed in the lwa ist.
According to Mibbit are the two servers on August 13, attacked: an adminserver and a server running a weblog turned. This would be the so-called nickserv-passwords of at least ten thousand users captured. Also of 9 administrators, passwords are captured. Mibbit allows users to enter their password to change it on other websites.
The hack has been claimed by Hack The Planet, a relatively old hackersgroepering. HTP agitates in a statement against Anonymous users. They would be much use Mibbit servers. The login details were for some time on Pastebin, but these have now been removed.
How the hackers exactly the Mibbit servers have managed to crack, is not yet known. This is also not known whether self-hosted Mibbit servers could be open to a similar attack.