On Thursday, Zero Day Initiative announced four flaws affecting two instant-messaging applications, three affecting Cerulean Studios Trillian Pro, and one affecting IBM Lotus Sametime. Zero Day Initiative is a part of TippingPoint and is controversial in that it pays researchers for finding flaws.
The first flaw in Trillian affects the header parsing code for the msn protocol and could allow remote attackers to execute arbitrary code. The advisory states "when processing the X-MMS-IM-FORMAT header, certain attributes are copied into a buffer located on the stack without any length verification which can eventually lead to code execution with the privileges of the user that is running the application."
The second flaw in Trillian affects XML parsing in talk.dll and could allow remote attackers to execute arbitrary code. The advisory states "when processing certain malformed attributes within...'IMG' tags, it is possible to overwrite past an allocated heap chunk which can eventually lead to code execution under the context of the currently user."
The third and final flaw in Trillian affects the FONT tag and exploitation may occur over the AIM network or via direct connections. The advisory states "the value for any attribute is copied into a stack based buffer via sprintf() which can result in a buffer overrun and can be subsequently leveraged to execute arbitrary code under the privileges of the logged in user."
In response, Cerulean Studios has released Trillian v184.108.40.206 to address these flaws.
The final IM vulnerability affects IBM Lotus Sametime and allows remote attackers to execute arbitrary code. The advisory says "a specially crafted URL can be passed into a vulnerable sscanf() function that will result in a stack overflow resulting in the ability to execute arbitrary code."
In response, IBM has issued an update.