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TONTOU
Announcement ID:
2026-08-10-001
Issue
Researchers from MIT CSAIL presented a paper titled “TONTOU: On the Exploitability of Time-of-Neutralization to Time-of-Use Windows” describing a class of speculative execution attacks they call TONTOU (Time-of-Neutralization to Time-of-Use) and an attack technique named INTERRUPT INJECTION.
Intel's assessment is that the behavior discussed in the paper is related to previously documented Branch History Injection (BHI) and Intra-Mode Branch Target Injection (IMBTI) scenarios addressed by Intel's existing guidance. Intel has not observed a real-world end-to-end attack on Intel processors and does not plan to provide additional mitigation guidance at this time. Intel's guidance remains unchanged across supported processor generations.
Additional Information
Acknowledgements
Intel thanks Daniël Trujillo and Mengjia Yan, MIT CSAIL, for reporting this issue.
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