AIM has a critical vulnerability that could allow attackers to compromise your computer and execute malicious code on it. The vulnerability is a buffer overflow within the handling of the "Away" messages which can be easily exploited. According to the Secuin.com advisory: "A malicious Web site can exploit this via the AIM URI handler by passing an overly long argument to the 'goaway?message' parameter," the advisory said. "Successful exploitation may allow execution of arbitrary code on a user's system when ? a malicious Web site is visited with certain browsers." Read more..