Yahoo Messenger hit with ninth zero-day exploit

The latest exploit on the Web can force-feed a malicious file to IM users

Attack code that targets Yahoo Messenger has been published on the Internet, a security researcher warned Wednesday, marking the ninth exploit aimed at the popular instant messaging software so far this year.

In a posting to the milw0rm.com Web site, someone identified as "shinnai" disclosed malicious Visual Basic code that allegedly lets attackers feed any file to users of the latest version of Messenger. The exploit code successfully executes on a fully-patched PC running Windows XP SP2, shinnai said, although the effect depends on the security settings of Internet Explorer (IE).

According to an e-mail alert from nCircle Network Security, hackers armed with the exploit could force-feed malware such as a Trojan horse to vulnerable users. It was nCircle that pegged the latest zero-day threat against Messenger as No. 9 for the year.

IE's security, however, can mitigate an attack. Users running the newer IE 7 with default security settings will probably be protected.

"This latest exploit is another data point in the strong trend toward IM client attacks," said Andrew Storms, nCircle's director of security operations. "IM vendors jockeying for market share are trying to lure new users with new features that also open up new risks to end users."

Storms was referring to the rash of instant messaging program flaws that have been uncovered in recent months. Yahoo Messenger, for example, has been patched several times this summer, while Microsoft decided less than a week ago on a mandatory upgrade that meant all users of its MSN Messenger and Windows Live Messenger clients had to update or lose access to the service.

Storms recommended that corporate IT admit that unauthorized instant messaging software is being used on their networks. "Enterprise IT teams that have been ignoring IM clients because they are not part of the 'official' infrastructure would be well advised to take steps to bring an IM client onto their supported platform and make sure their antivirus and spyware vendors work with their selected client," he said in an e-mail.

Yahoo, which patched Messenger twice last month, did not immediately respond to a request for confirmation of the newest flaw and queries about a patch timeline.

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

Computerworld
Show Comments

Father’s Day Gift Guide

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?