CVE-2024-28836: Trustedfirmware Mbed TLS

Medium severity, CVSS 5.4. 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 negotiating the TLS version on the server side, it can fall back to the TLS 1.2 implementation of the protocol if it is disabled. If the TLS 1.2 implementation was disabled at build time, a TLS 1.2 client could put a TLS 1.3-only server into an infinite loop processing a TLS 1.2 ClientHello, resulting in a denial of service. If the TLS 1.2 implementation was disabled at runtime, a TLS 1.2 client can successfully establish a TLS 1.2 connection with the server.

Affected products

• Trustedfirmware Mbed TLS: from 3.5.0, before 3.6.0 (fixed in 3.6.0)

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