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AOL Instant Messenger vulnerable to buffer overflow via numerous fonts sent to client followed by &lt HR&gt

Vulnerability Note VU#530299

Original Release Date: 2002-01-14 | Last Revised: 2002-01-14


AOL Instant Messenger (AIM) is an application that allows one peer to communicate with another. A vulnerability exists that can crash the client window and in some cases the operating system(OS).


AIM for Windows stores font names in the messages sent from one client to another. By using numerous fonts, and sending a html division line <HR>, an attacker can cause the victim's client to crash.


By repeatedly sending this message, a continued denial of service can be caused.


This has been resolved in AIM for Windows beta version 4.8.2540.

AIM permits the user to only accept messages from known/trusted peers. Enable this feature.

Vendor Information


AOL Time Warner Affected

Notified:  October 17, 2001 Updated: January 14, 2002



Vendor Statement

This is fixed in our most recent Win AIM Beta 4.8.2540 posted Nov. 19th.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.


Win AIM Beta 4.8.2540 was posted on Nov. 19th, 2001.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

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This vulnerability was discovered by Robbie Saunders.

This document was written by Jason Rafail.

Other Information

CVE IDs: None
Severity Metric: 9.45
Date Public: 2001-10-06
Date First Published: 2002-01-14
Date Last Updated: 2002-01-14 18:28 UTC
Document Revision: 12

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