Description
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.
Affected products
arm: mbed tls; arm: tf-psa-crypto
References4
- mbed-tls.readthedocs.io/en/latest/security-advisories/ Vendor Advisory
- mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-s… Vendor Advisory
- github.com/Mbed-TLS/TF-PSA-Crypto/releases Release Notes
- github.com/Mbed-TLS/mbedtls/releases Release Notes
Metrics
- CVSS 3.1
-
5.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 21 · as of 12 November 2026
- CWE
- CWE-385
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