CVE-2025-66442
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.
Published Apr 1, 2026 · updated Jun 17, 2026 · arm mbed tls
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.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Apr 1, 2026 · NIST NVD
Detected
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.
Jun 17, 2026 · NIST NVD
Updated
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
- cpe arm/mbed tlsversion unspecified
- cpe arm/tf-psa-cryptoversion unspecified
Sources
- CVE.orgVulnerability recordCVE-2025-66442
Official CVE identifier
cve.org - NIST NVDVulnerability recordCVE-2025-66442
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.
nvd.nist.gov