CVE-2018-1000520: Arm Mbed TLS

High severity, CVSS 7.5. EPSS: 0.7% chance of exploitation in the next 30 days.

ARM mbedTLS version 2.7.0 and earlier contains a Ciphersuite Allows Incorrectly Signed Certificates vulnerability in mbedtls_ssl_get_verify_result() that can result in ECDSA-signed certificates are accepted, when only RSA-signed ones should be.. This attack appear to be exploitable via Peers negotiate a TLS-ECDH-RSA-* ciphersuite. Any of the peers can then provide an ECDSA-signed certificate, when only an RSA-signed one should be accepted..

Affected products

• Arm Mbed TLS: up to and including 2.7.0

Published 2018-06-26. Last modified 2026-06-17.