CVE-2026-5507: wolfSSL

Medium severity, CVSS 4.0. EPSS: 0.2% chance of exploitation in the next 30 days.

When restoring a session from cache, a pointer from the serialized session data is used in a free operation without validation. An attacker who can poison the session cache could trigger an arbitrary free. Exploitation requires the ability to inject a crafted session into the cache and for the application to call specific session restore APIs.

Affected products

• wolfSSL wolfSSL: up to and including 5.9.0

Published 2026-04-09. Last modified 2026-06-17.