Multiple security holes found in Firefox

Internet users surfing with Firefox must urgently upgrade to avoid over 20 security holes in the open source browser, the Mozilla Foundation has warned.



The multiple vulnerabilities apply to any product based on Mozilla components that was released before the Firefox 1.5.0 x product line, including the Thunderbird e-mail client and SeaMonkey suite.



The most severe exploit could allow a remote hacker to execute arbitrary code on an affected system or cause a denial-of-service condition.



Less critical exploits include the potential for malicious people to launch cross-site scripting and phishing attacks, with a view to stealing a user's personal information.



Firefox browsers also run the risk of having sensitive files unknowingly uploaded from their PC, thanks to an error in the handling of file upload controls.



Successful exploitation of the 20 other vulnerabilities intrinsic to Mozilla products can cause memory corruption, a heap-based buffer overflow and "interaction with a browser interface which is not visible."



Such is the warning from security experts at Secunia, which alongside the US Computer Readiness Team, has issued detailed advisories on each exploit, the first of which was reported to Mozilla in January.



The holes in Firefox and Mozilla-developed tools are thought to have dealt the most significant blow to the security-shrewd reputation of the Foundation's most visible open source browser.



For all its differences to Internet Explorer, the popular alternative browser shared the tradition of being exposed by freelance security agents, as Mozilla explained.



"An anonymous researcher for TippingPoint and the Zero Day Initiative discovered an integer overflow triggered by the CSS letter-spacing property," the Foundation said.



"This results in under-allocating memory and ultimately a heap buffer overflow which could be exploited to run code of the attacker's choice.



"The overflow condition itself does not require JavaScript and thus could affect Thunderbird via received mail, but without scripting to prepare memory it may not be possible to exploit this condition in mail."



Mozilla says Firefox 1.5.0.2 is now available for Windows, Mac, and Linux for free download and immediate fix for security issues, common crashes and memory leaks.

























Apr 19, 2006