Adobe patches under-attack Reader bug

Ships emergency update to plug a hole hackers have exploited for weeks using rigged PDFs

Adobe today issued an emergency update for its popular Reader PDF software that patched two critical vulnerabilities, including one attackers have exploited for weeks.

The more notable flaw fixed in Reader 9.4.1 for Windows and Mac OS X was a bug that hackers have been leveraging since late October using malicious PDF documents. Those attacks have taken advantage of a flaw in Reader's "authplay" component. Authplay is the interpreter that renders Flash content embedded within PDF files.

Successful attacks have dropped a Trojan horse and other malware on victimized Windows PCs.

Authplay has been targeted by malware makers several times this year, most recently in June. Then, Adobe shipped an emergency patch for Flash Player within a week, and followed with a fix for Reader and Acrobat two weeks later.

Adobe followed the same general timeline this time, patching Flash Player first on Nov. 4, then Reader and Acrobat today.

Adobe has defended its two-stage patching -- which some have questioned because active authplay exploits are typically aimed at Reader, not Flash -- by explaining that the fix was first crafted by its Flash development team. The patched "authoplay.dll" file was then handed off to the Reader group to integrate and test with their product.

The second vulnerability addressed Tuesday had been disclosed on the Full Disclosure security mailing list earlier this month. At the time, Adobe said that the flaw could be used to crash Reader, but not Acrobat, and said it was unsure whether an exploit could compromise a computer running the PDF program.

Adobe repeated that analysis today. "These updates resolve a memory corruption vulnerability that could potentially lead to code execution," the company said in an advisory accompanying the updates.

Although Adobe tries to hew to a quarterly patch schedule for Reader and Acrobat, at times it's scuttled those plans to issue rush fixes for critical bugs. That wasn't the case here: Adobe made it a point to remind users that it will still release its next regularly-scheduled Reader update on Feb. 8, 2011.

Only the Windows and Mac versions of Reader and Acrobat were patched today. An updated Reader for Linux/Unix won't ship until Nov. 30. Adobe also postponed a patch for the older Adobe 8.x, which is vulnerable to the second bug.

"Adobe plans to address Adobe Reader version 8.x in the next release," the advisory read.

Neither bug affected the Android version of Reader that Adobe launched in August.

Reader was last patched Oct. 5 in a 23-fix update one security expert called a "double-whammy."

Adobe Reader and Acrobat for Windows and Mac OS X can be downloaded using the links included in Tuesday's advisory. Alternately, users can call up the programs' built-in update mechanisms to grab the new versions.

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 (US)
Show Comments

Brand Post

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?