Menu
Yahoo patches Messenger zero-day flaws

Yahoo patches Messenger zero-day flaws

Yahoo Inc. late yesterday released a new version of its Messenger instant messaging client to patch a pair of zero-day vulnerabilities that let attackers grab control of a Windows PC with little or no help from the user.

The bugs in Messenger's Webcam ActiveX controls were reported Wednesday by eEye Digital Security Inc.; within hours a researcher identified only as "Danny" had posted exploit code for both flaws on a security mailing list.

A day later, Yahoo had patched Messenger, posted the new version on its site and urged everyone to download and install it. The update isn't mandatory, however. "Over the next several weeks, users worldwide will be prompted to update to a new version of Messenger upon signing into the service," a company spokesman said in an e-mail. "If you choose not to update, the vulnerability will still exist."

Nor is the update automatic, which means that users with older versions of Yahoo Messenger installed, but who no longer use the IM client, may never receive the warning. Infrequent users of Messenger will also be at risk until they update Yahoo's software.

A Yahoo security advisory also said that attacks would most likely come via malicious Web sites. "Some impacts of [the vulnerabilities] might include the introduction of executable code, being involuntarily logged out of a chat and/or instant messaging session, and the crash of an application such as Internet Explorer."

Because Yahoo had posted the patched edition, eEye updated its advisory Friday with additional information on the vulnerabilities and how they could be exploited by attackers. Normally, said eEye, the two buggy ActiveX controls are used only when viewing or streaming webcam video content to and from Messenger.

"But they are incorrectly marked safe for scripting and [so] can be instantiated by any Web site," eEye's new advisory read. That means an attacker with a malicious site can entice users there, then call on the flawed ActiveX controls without firing up Messenger and triggering the update alert. Also today, Danny the researcher updated his exploit code after others said they were unable to duplicate the vulnerabilities. Those testers have reported that the exploit updates work.

According to eEye, all versions of Windows are vulnerable to attack, except for Vista, since Yahoo has not yet finished a version for that operating system.

The updated Messenger for Windows 98, 2000, Millennium and XP is available for download.


Follow Us

Join the newsletter!

Or
Error: Please check your email address.

Featured

Slideshows

Bumper channel crowd kicks off first After Hours of 2018

Bumper channel crowd kicks off first After Hours of 2018

After Hours made a welcome return to the channel social calendar with a bumper crowd of partners, distributors and vendors descending on The Jefferson in Auckland to kick-start 2018. Photos by Gino Demeer.

Bumper channel crowd kicks off first After Hours of 2018
Looking back at the top 15 M&A deals in NZ during 2017

Looking back at the top 15 M&A deals in NZ during 2017

In 2017, merger and acquisitions fever reached new heights in New Zealand, with a host of big name deals dominating the headlines. Reseller News recaps the most important transactions of the Kiwi channel during the past 12 months.

Looking back at the top 15 M&A deals in NZ during 2017
Kiwi channel closes 2017 with After Hours

Kiwi channel closes 2017 with After Hours

The channel in New Zealand came together to celebrate the close of 2017, as the final After Hours played out in front of a bumper Auckland crowd.

Kiwi channel closes 2017 with After Hours
Show Comments