Saint Sinkclose, Who Descended to Ring -2

Patron of AMD processors, System Management Mode, and malware that survives a reinstall.

Life

On 9 August 2024, at DEF CON, Enrique Nissim and Krzysztof Okupski of IOActive showed a flaw that had sat in AMD processors for nearly two decades. Anyone who already had kernel privileges could abuse a forgotten feature to run code in System Management Mode, the deepest and most privileged level of the CPU. From there one could plant bootkits invisible to antivirus software, able to survive even a reinstall of the operating system.

Prayer

O Saint Sinkclose, who dwells beneath the kernel and beneath the hypervisor, keep our firmware updated and our rings where they belong. Amen.

How to celebrate

Celebrated by installing AMD firmware and microcode updates and, for the models left unpatched, lighting a candle.

The deeper the bug goes, the higher the bill.