Unpatched Firfox 1.5 exploit made public

Last night I decided to upgrade my firefox installation from 1.07 to the newly released 1.5 version. It was a good move to me since I saw the preview for version 1.5 with much cleaner interface. Some of my addons/ extension doesn't seems to work though... had to disable a couple of them but I'm pretty sure that they come out with an update that works with the new version.

Apart from the RSS subscription button moved from bottom right hand corner to the location bar (wierd change for me at first), I was happy with the new version. I love how you have a centralized place to clear of private data like your history, saved sessions, etc.. pretty handy to erm cover your track :P

Then this morning I was at CNET's News.com and the following article hit me! They have not come out with a fix as when I'm typing this.. but I'm not worried.. just a browser crash nothing to shout about.. unless it can cause me another worm infection then I'll removing version 1.5 faster than you can say mozilla!

Unpatched Firfox 1.5 exploit made public

By Dawn Kawamoto
Source : CNET news.com

Exploit code for the latest version of open-source browser Firefox was published Wednesday, potentially putting users at risk of a denial-of-service attack.

The exploit code takes advantage of a bug in the recently released Firefox 1.5, running on Windows XP with Service Pack 2. Firefox, which initially debuted over a year ago, has moved swiftly to capture 8 percent of the browser market.

The latest Firefox flaw exists in the history.dat file, which stores information from Web sites users have visited with the Firefox 1.5 browser, according to a posting on the Internet Storm Center, which monitors online threats.

"If the topic of a page is crafted to be long enough, it will crash the browser each time it is started after going to such a page," according to the Internet Storm Center posting. "Once this happens, Firefox will be unable to be started until you erase the history.dat file manually."

In testing Firefox 1.5 without a system running McAfee security software, the Firefox 1.5 browser would stall and not respond to a user's mouse, said Johannes Ullrich, chief research officer for the Sans Institute, which runs the Internet Storm Center.

"Users have to kill out of the browser and start over again. This stalled browser creates a DOS (denial of service) condition," Ullrich said.

Packet Storm, the security group that initially published the proof-of-concept exploit code, noted that in addition to the potential denial-of-service attack that could follow a buffer overflow, systems may also be subject to a malicious execution of code.

Ullrich, however, said while the potential may exist, it has not been proven either way that malicious code could be executed.

Mozilla Foundation, which released Firefox, said it was not able to confirm the browser would crash or be at risk of a DOS attack, after visiting certain Web sites. And Mozilla has not received any reports from users of such a problem, said Mike Schroepfer, vice president of engineering for Mozilla Corp.

He added that Firefox 1.5 can be slugglish on its next start-up, due to a bug in the history.dat, but it is not a security problem.

"We have gotten no independent verification that it crashes (Firefox), but there have been a lot of attempts to try," Schroepfer said.