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At the Defcon hacker conference tomorrow, Enrique Nissim and Krzysztof Okupski, researchers from the security firm IOActive, plan to present a vulnerability in AMD chips they're calling Sinkclose. The flaw would allow hackers to run their own code in one of the most privileged modes of an AMD processor, known as System Management Mode, designed to be reserved only for a specific, protected portion of its firmware. IOActive's researchers warn that it affects virtually all AMD chips dating back to 2006, or possibly even earlier.
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‘Sinkclose’ Flaw in Hundreds of Millions of AMD Chips Allows Deep, Virtually Unfixable Infections
Researchers warn that a bug in AMD’s chips would allow attackers to root into some of the most privileged portions of a computer—and that it has persisted in the company’s processors for decades.