Mozilla disputes Firefox flaws

A 'critical' IE bug revealed Monday also affects Apple's Safari browser

Mozilla's security chief Tuesday panned a pair of Firefox bugs revealed Monday as low-level threats but hours later changed her mind and said that when used together, they could pose a greater risk.

The researcher who disclosed the vulnerabilities agreed with her. Mostly.

Michal Zalewski, who regularly publishes browser flaw findings, on Monday posted details on the Full-disclosure mailing list about four browser vulnerabilities, including two affecting Firefox. He categorized one as a "major" threat, and he saw the other as only a "medium" threat.

In an entry on the Mozilla security blog -- which debuted last week -- Window Snyder, the company's chief security officer, said the more serious of the two bugs found by Zalewski was no more than a spoofing vulnerability and deserved only a "low" rating. "This is unsafe because it could be used to lure a user to enter content into the spoofed frame, but does not result in code execution," said Snyder. "[For example], this might be used with phishing attacks."

Her take doesn't jibe with Zalewski's contention that the flaw can be used to stick malicious code onto the victimized computer. "By my book, [this is] more serious than just spoofing, so I marked it as 'major,' whereas Mozilla still considers it to be a typical case of spoofing ('low')," said Zalewski in an e-mail interview Wednesday. "But it would be inaccurate to say that Window's assessment contradicts my analysis."

Later Tuesday, Snyder updated her blog, saying that after further review, "these two bugs may be used together to allow an attacker to access any file the user has access to on the system. If this is the case, that may change the severity rating to 'medium.'"

Zalewski dismissed the idea that he and Mozilla's Snyder were at odds, and instead turned attention to what he thinks is most important. "All in all, I think we pretty much agree here," he said. "The big issue [of the four vulnerabilities] was the Microsoft Internet Explorer flaw. The other three are important, but not critical."

According to entries in Mozilla's Bugzilla, the more serious of the two Firefox flaws has not yet been assigned to someone for a fix. Snyder, meanwhile, said that the Mozilla security team is looking into changes to improve content handler management, the root cause of the bug she pegged as "low."

Zalewski on Monday noted on the Full-disclosure mailing list that it appears Apple Inc.'s Safari browser is also vulnerable to same bug he found in IE6 and IE7 and labeled "critical." Tuesday, Kevin Finisterre, a researcher known for the "Month of Apple Bugs" project in January, confirmed Zalewski's Safari suspicions.

Apple officials did not reply to a request for comment.

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.
Gregg Keizer

Gregg Keizer

Computerworld
Show Comments

Father’s Day Gift Guide

Brand Post

Bitdefender 2019

Bitdefender solutions stop attacks before they even begin! Get cybersecurity that 500 MILLION users already have and trust.

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Luke Hill

MSI GT75 TITAN

I need power and lots of it. As a Front End Web developer anything less just won’t cut it which is why the MSI GT75 is an outstanding laptop for me. It’s a sleek and futuristic looking, high quality, beast that has a touch of sci-fi flare about it.

Emily Tyson

MSI GE63 Raider

If you’re looking to invest in your next work horse laptop for work or home use, you can’t go wrong with the MSI GE63.

Laura Johnston

MSI GS65 Stealth Thin

If you can afford the price tag, it is well worth the money. It out performs any other laptop I have tried for gaming, and the transportable design and incredible display also make it ideal for work.

Andrew Teoh

Brother MFC-L9570CDW Multifunction Printer

Touch screen visibility and operation was great and easy to navigate. Each menu and sub-menu was in an understandable order and category

Louise Coady

Brother MFC-L9570CDW Multifunction Printer

The printer was convenient, produced clear and vibrant images and was very easy to use

Edwina Hargreaves

WD My Cloud Home

I would recommend this device for families and small businesses who want one safe place to store all their important digital content and a way to easily share it with friends, family, business partners, or customers.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?