CVE-2026-25835: Arm Mbed TLS

High severity, CVSS 7.7. EPSS: 0.2% chance of exploitation in the next 30 days.

Mbed TLS before 3.6.6 and TF-PSA-Crypto before 1.1.0 misuse seeds in a Pseudo-Random Number Generator (PRNG).

Affected products

• Arm Mbed TLS: from 2.18.0, before 3.6.6 (fixed in 3.6.6)
• Trustedfirmware Mbed TLS: version 4.0.0 only
• Trustedfirmware Tf-Psa-Crypto: before 1.1.0 (fixed in 1.1.0)

Published 2026-04-01. Last modified 2026-06-17.