CVE-2025-66442
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.1epss 0.3%
exploitation probability
0.3%top 81% of all CVEs
observed exploitation
nono source reports it
In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected products
n/a · n/aReferences
https://github.com/Mbed-TLS/mbedtls/releaseshttps://github.com/Mbed-TLS/TF-PSA-Crypto/releaseshttps://mbed-tls.readthedocs.io/en/latest/security-advisories/https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2026-03-compiler-induced-constant-time-violations/