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Cisco has patched its Jabber conferencing and messaging application against a critical vulnerability that made it possible for attackers to execute malicious code that would spread from computer to computer with no user interaction required. Again.

The vulnerability, which was first disclosed in September , was the result of several flaws discovered by researchers at security firm Watchcom Security. First, the app failed to properly filter potentially malicious elements contained in user-sent messages. The filter was based on an incomplete blocklist that could be bypassed using a programming attribute known as onanimationstart.

Messages that contained the attribute passed directly to DOM of an embedded browser. Because the browser was based on the Chromium Embedded Framework, it would execute any scripts that made it through the filter.