INTERRUPT INJECTION enables Spectre v2 branch predictor re-poisoning
Source headline: New Interrupt Injection Attack Can Bypass Spectre v2 Defenses on Intel and AMD CPUs
Intelligence Summary
MIT CSAIL researchers describe INTERRUPT INJECTION, a timing-based side-channel technique. By triggering a hardware interrupt at a precise moment, an unprivileged Linux program can land during the period when defenses for Spectre v2 are sanitizing the branch predictor. After the kernel’s mitigation runs, the attacker can re-poison the predictor and regain exploitable behavior. The bypass is demonstrated on Intel and AMD systems, including AMD Zen 2 with Linux 6.14 and default Spectre v2 mitigations. This matters because it weakens common Spectre v2 assumptions and may require updated kernel mitigations or kernel timing hardening.
Recommended Action
Review affected assets, schedule urgent remediation, and monitor related indicators.