MIT Researchers Uncover New Spectre-Style CPU Attack, TONTOU, Affecting Intel and AMD Processors

Researchers at MIT's Computer Science and Artificial Intelligence Laboratory have identified a novel Spectre-style CPU attack named TONTOU (Time-of-Neutralization to Time-of-Use). This technique exploits a brief 'post-neutralization window' after a processor clears or isolates branch predictor state but before the prediction hardware is reused, allowing it to bypass some existing branch predictor defenses on Intel and AMD processors.