CVE-2026-5264: wolfSSL

Critical severity, CVSS 9.8. EPSS: 0.6% chance of exploitation in the next 30 days.

Heap buffer overflow in DTLS 1.3 ACK message processing. A remote attacker can send a crafted DTLS 1.3 ACK message that triggers a heap buffer overflow.

Affected products

• wolfSSL wolfSSL: before 5.9.1 (fixed in 5.9.1)

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