New Interrupt Injection Attack Can Bypass Spectre v2 Defenses on Intel and AMD CPUs

Researchers disclosed a microarchitectural attack named "Interrupt Injection" that times interrupts to land between branch-predictor sanitization (Safe-RET/equivalents) and kernel use, enabling speculative kernel memory leakage on affected AMD Zen processors; MIT CSAIL demonstrated leaks against Linux, AMD issued a bulletin and a kernel patch, and Intel did not require additional mitigation.