America Online Inc. has released a beta version of AOL Instant Messenger that fixes a critical security hole that could open users to remote attack.
Security researchers had found that AIM 5.5 for Windows, and possibly earlier versions, was vulnerable to an attacker executing arbitrary code.
An attacker could initiate a buffer overflow through AIMs "Away" feature if a user were to click on a malicious link sent in an instant message. The "Away" features allows AIM users to send automatic messages about their presence status.
AOL spokesman Andrew Weinstein said the Dulles, Va., company knew of no active exploits of the vulnerability. Security research company iDEFENSE Inc., which put out an advisory this week, had informed AOL of the issue about a month ago, giving AOL an opportunity to plug the hole, Weinstein said.
The fix also will be incorporated into the full release of AIM 5.9, which a spokeswoman said is expected in early fall.
"We will continue to upgrade the product, and there will be a full release in future, but we encourage users to download the beta if they have any concerns about security," Weinstein said. "We advise users of IM and e-mail to be extremely cautious about clicking any link, especially if its from people they dont know."
Besides the security fix, the AIM 5.9 beta also includes a new feature, "Youve Got Picture," for storing and sharing digital photos through IM, as well as hundreds of additional buddy icons.