"AMD paints the 12.6 WHQL update as more of a maintenance update, and sure enough, the release notes outline a fairly meaty list of bug fixes. Among them is the plugging of a potential security vulnerability. AMD doesn't say what the vulnerability is, only how it came to discover it:

CERT recently approached AMD with information pertaining to what they believed to be a possible video driver vulnerability exposed by non-default settings of the Microsoft Enhanced Mitigation Experience Toolkit (EMET). EMET is a security test tool that allows system administrators to create test conditions to validate correct behavior of system components or indicate potential weak points."

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