HIGHCVE-2026-33218Published Modified CNA GitHub_M
CVE-2026-33218: NATS has pre-auth server panic via leafnode handling
NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, a client which can connect to the leafnode port can crash the nats-server with a certain malformed message pre-authentication. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, disable leafnode support if not needed or restrict network connections to the leafnode port, if plausible without compromising the service offered.
Metrics
- CVSS v3.1
- 7.5
- Severity
- HIGH
- Fixed in
- —
- Affected Products
- 1
Affected packages
- nats-io / nats-server< < 2.11.15 · >= 2.12.0-RC.1, < 2.12.6
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H