Intel processors (vector register sampling): Stale values left in vector registers can be sampled by other contexts

Impact

Stale values left in vector registers can be sampled by other contexts, leaking data across the process and enclave boundary. Lower yield than the fill-buffer attacks but it targets the vector registers - which is where floating-point tensor data lives on an AI node.

Who can reach it

Local code on the same physical core as the victim.

What to do

Microcode update plus the OS buffer-clearing mitigation, then reboot. Microcode is late-loadable at boot; no OEM BIOS release strictly needed.

References

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