Ryan McGeehan has reported a vulnerability in AOL Instant Messenger (AIM), which can be exploited by malicious people to compromise a user's system.

The vulnerability is caused due to a boundary error within the handling of "Away" messages and can be exploited to cause a stack-based buffer overflow by supplying an overly long "Away" message (about 1024 bytes). A malicious website can exploit this via the "aim:" URI handler by passing an overly long argument to the "goaway?message" parameter.

Successful exploitation allows execution of arbitrary code on a user's system when e.g. a malicious website is visited with certain browsers.

The vulnerability has been confirmed in version 5.5.3595. Other versions may also be affected.

NOTE: Various other issues were also reported, where a large amount of resources can be consumed on a user's system.

Solution
The vendor has contacted Secunia and recommends that users install a beta version, which addresses the vulnerability, or remove support for the "aim:" URI handler by deleting the "HKEY_CLASSES_ROOT\aim" registry key.
Further details available to Secunia VIM customers

Provided and/or discovered by
The vulnerability was discovered independently by the following around the same time:
1) Ryan McGeehan and Kevin Benes, TheBillyGoatCurse.com.
2) Matt Murphy

Changelog
Further details available to Secunia VIM customers

Other references
Further details available to Secunia VIM customers

Deep Links
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