Original URL: http://www.theregister.co.uk/2006/10/05/mozilla_flaw_joke/

Mozilla flaws more joke than jeopardy

Firefox attack a 'stand up comedy routine'

By Robert Lemos

Posted in Security, 5th October 2006 08:42 GMT

Two presenters razzed developers of the open source Mozilla browser this weekend at the ToorCon hacking convention in San Diego with claims that the browser's Javascript implementation is flawed, but the lecture appears to have been more stand-up comedy routine than substantiative research.

The two researchers - college student and Six Apart developer Mischa Spiegelmock and hacker Andrew "Wbeelsoi" who also uses the handle "Weev" - appeared to demonstrate a remotely exploitable flaw in the Javascript implementation of the Mozilla Firefox browser during their Saturday presentation.

However, the duo have not been able to actually get the vulnerability to result in control of a computer, Spiegelmock said in a statement posted to the Mozilla developer blog.

The presentation was intended mainly as a joke, Spiegelmock said in the statement, in which he apologised.

"The main purpose of our talk was to be humourous," the 19-year-old researcher said in the statement. "As part of our talk we mentioned that there was a previously known Firefox vulnerability that could result in a stack overflow ending up in remote code execution. However, the code we presented did not in fact do this, and I personally have not gotten it to result in code execution, nor do I know of anyone who has."

The presentation had gained some credence because an increasingly number of flaws have been found in the Javascript implementations of several browsers, including Firefox, with researchers warning that flaws in the technology could allow web worms the ability to gather information about a victim's network and to gain some access to a user's computer.

The humourous attack on Mozilla also came as software giant Microsoft scrambled to deal with its own zero-day attacks on its Internet Explorer browser and Windows operating system.

Spiegelmock's and Wbeelsoi's claims were widely mirrored by numerous blogs and news aggregators after a News.com article covered the presentation. The duo called Mozilla's implementation of Javascript a "complete mess" and "impossible to patch", according to the article. The hackers reportedly claimed to have 30 more Firefox vulnerabilities that he intended to keep to themselves to set up "communication networks for black hats".

Spiegelmock and his employer, blog developer and service provider Six Apart, backed off those statements on Monday.

"I do not have 30 undisclosed Firefox vulnerabilities, nor did I ever make this claim," Spiegelmock said in the statement posted to Mozilla's blog late Monday night. "I have no undisclosed Firefox vulnerabilities. The person who was speaking with me made this claim, and I honestly have no idea if he has them or not."

According to a source familiar with the matter, Spiegelmock does not have any other information about vulnerabilities outside of the denial-of-service vulnerability included in the presentation. Moreover, the college student has disclosed all details about the flaws to the Mozilla Foundation. Neither Spiegelmock nor Wbeelsoi responded to emailed interview requests.

Six Apart downplayed the style of the presentation as a prank.

"Mischa is a young man - he meant the presentation in jest," said Jane Anderson, spokeswoman for Six Apart.

Members of the audience assumed that the two presenters were having a bit of fun, rather than actually criticising the Mozilla browser's code.

"I wasn't pay much attention to what they said they had, because the whole thing was coming across as a comedy show," said Mark Loveless, security architect for Vernier Networks, who saw the presentation. "They had a whole bunch of things in there that was intended to be a joke, trying to get laughs. I didn't have any problems with the talk, I thought it was hilarious, and I didn't take is seriously."

The presentation came a week after security firm Symantec, the owner of SecurityFocus, released its bi-annual Internet Security Threat Report, which found - among other trends - that Mozilla's browsers had the most vulnerabilities. While 47 flaws were found in the open source browser, only 38 were disclosed by Microsoft for its Internet Explorer browser during the same period.

However, the data also showed the Mozilla fixed its vulnerabilities much more quickly. The metric used by Symnatec, termed "window of exposure", measures the time a company takes to patch a flaw in its software, starting from the moment a public exploit is released for the vulnerability. Microsoft took nine days on average - the slowest time - to patch its browser, while Mozilla fixed the flaws in its browser in a single day on average - the fastest time.

The Mozilla Foundation would not comment on the ToorCon presentation except to assure users that they are looking into the flaw report.

"So far we've been able to reproduce a denial of service issue based on the information they gave during their talk. In some cases this causes a crash based on an out of memory error," Window Snyder, chief security officer for the Mozilla Foundation, said in an earlier blog post. "Based on the information we have at this time we have not been able to confirm whether an attacker can achieve code execution. We’'re still investigating and we'll keep you updated."

The warnings of flaws in Mozilla's Firefox do not change the security equations, security researcher Thor Larholm stated in a post on the SecuriTeam blogs. Vulnerabilities happen and Mozilla responds to security issues quickly, he said.

Vernier's Loveless echoed the sentiment.

"I'm no more worried about Mozilla security today than I was before the con," Loveless said. "Odds are, there are 30 flaws in the browser, but whether they have them or someone else has them, you know...the bugs are out there regardless."

And Loveless said he intends to keep on using Firefox just the way he always has - with Javascript turned off.

This article originally appeared in Security Focus.

Copyright © 2006, SecurityFocus