CVE-2026-13698 - Server memory leak via repeated tls-crypt-v2 HARD_RESET_CLIENT_V3 packets
A memory leak in the tls_crypt_v2_extract_client_key function in OpenVPN 2.x allows remote attackers with a valid
tls-crypt-v2 client key to cause a denial of service (memory exhaustion) via repeated HARD_RESET_CLIENT_V3 packets
when tls-crypt-v2 is enabled because the server fails to free existing key contexts before overwriting them during
session re-initialisation.
OpenVPN version 2.5.0 through 2.6.20 and 2.7_alpha1 through 2.7.4 are affected. This is fixed in versions 2.6.21 and 2.7.5.
CVE Record: CVE-2026-13698
Github:
Release notes:
Reported-By: Max Fillinger (maximilian.fillinger@sentyron.com)