constant-time-testing

Timing attacks exploit variations in execution time to extract secret information from cryptographic implementations. Unlike cryptanalysis that targets theoretical weaknesses, timing attacks leverage implementation flaws - and they can affect any cryptographic code.

Timing attacks were introduced by Kocher in 1996. Since then, researchers have demonstrated practical attacks on RSA (Schindler), OpenSSL (Brumley and Boneh), AES implementations, and even post-quantum algorithms like Kyber.

| Constant-time | Code path and memory accesses independent of secret data | | Timing leakage | Observable execution time differences correlated with secrets | | Side channel | Information extracted from implementation rather than algorithm | | Microarchitecture | CPU-level timing differences (cache, division, shifts) |

Тестирование с постоянным временем обнаруживает побочные каналы синхронизации в криптографическом коде. Используйте при аудите криптографических реализаций на предмет временных уязвимостей. Источник: trailofbits/skills.