CVE-2024-28755: Trustedfirmware Mbed TLS

Medium severity, CVSS 6.5. EPSS: 0.4% chance of exploitation in the next 30 days.

An issue was discovered in Mbed TLS 3.5.x before 3.6.0. When an SSL context was reset with the mbedtls_ssl_session_reset() API, the maximum TLS version to be negotiated was not restored to the configured one. An attacker was able to prevent an Mbed TLS server from establishing any TLS 1.3 connection, potentially resulting in a Denial of Service or forced version downgrade from TLS 1.3 to TLS 1.2.

Affected products

• Trustedfirmware Mbed TLS: from 3.5.0, up to and including 3.6.0

Published 2024-04-03. Last modified 2026-06-17.