Google security hackers have confirmed a confidential computing compromise that targets AMD Zen-based devices.

Chipmaking giant AMD has confirmed it recently patched a high-severity vulnerability affecting its Zen 1 to Zen 4 CPUs.

Malicious microcode vulnerability discovered, fixes rolling out for Epycs at least Googlers have not only figured out how to break AMD's security – allowing them to load unofficial microcode into its processors to modify the silicon's behavior – but also demonstrated this by producing a microcode patch that makes the chips always output 4 when asked for a random number.