AMD fixed the "Purple Pill" exploit with Catalyst 7.8 Release
 

Last week, reports of an AMD ATI Catalyst driver vulnerability appeared around the web. The vulnerability affected the ATI Catalyst driver package and triggered by the Purple Pill tool, which was a proof-of-concept, and allowed malicious kernel tampering in Windows Vista.

The Purple Pill came from kernel developer Alex Ionescu. Ionescu released the tool while not realizing AMD had yet to patch a flaw in its ATI Catalyst driver package. The tool allowed users to load unsigned drivers in Windows Vista. Theoretically, a malicious user could tamper with the Vista kernel using a rootkit that would piggyback to the ATI driver.

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