Mozilla has reacted quickly to patch a zero-day vulnerability in its Firefox browser software.
The security flaw was used to run a drive-by-download attack so that Firefox fans visiting the website for the Nobel Peace prize were exposed to malware on Tuesday.
The mechanism of the attack, detected by security researchers on Tuesday, is blocked with the release of the latest version of the open source web browser, Firefox 3.6.12. Mozilla has also released a cross-platform update for the earlier version 3.5.x version of the browser that addresses the same security hole.
The underlying vulnerability affects Mac OS X and Linux as well as Windows boxes running Firefox, hence the need for a cross-platform update even though the Nobel Prize site attack was Windows-specific. Firefox 4 beta is immune from the vulnerability, hence there's no need to update existing pre-release versions of the browser, due to make its delayed debut in early 2011.
Mozilla credits Norwegian security vendor Telenor with discovering the flaw.
More details on the attack can be found in a blog post by anti-virus scanner firm Avira here.
Avira dismisses the malware that featured in the attack as an amateurish and unreliable effort. "It is currently unclear why obviously a script-kiddie-like malware abuses such a valuable zeroday vulnerability; usually cyber criminals abuse them for profitable malware," it said. ®