Security researchers have discovered a vulnerability that affects almost all AMD CPUs, allowing access to some of the deepest parts of the chip. Named 'Sinkclose', the flaw allows attackers that already have kernel-level access to modify SMM (System Management Mode) settings even with existing protections enabled.
Attackers could use the flaw to install malware that would be virtually undetectable, and extremely difficult to remove. However, gaining kernel access in the first place is no easy task, and AMD has already begun releasing fixes for some of the affected chips (via Bleeping Computer).
