Unrated severityNVD Advisory· Published Nov 21, 2025· Updated Dec 8, 2025
Constant Time Issue with Xtensa-based ESP32 and X22519
CVE-2025-12888
Description
Vulnerability in X25519 constant-time cryptographic implementations due to timing side channels introduced by compiler optimizations and CPU architecture limitations, specifically with the Xtensa-based ESP32 chips. If targeting Xtensa it is recommended to use the low memory implementations of X25519, which is now turned on as the default for Xtensa.
Affected products
1Patches
0No patches discovered yet.
Vulnerability mechanics
AI mechanics synthesis has not run for this CVE yet.
References
1News mentions
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