Vulnerability Description
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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linuxfoundation | Nats-Server | < 2.11.15 |
Related Weaknesses (CWE)
References
- https://advisories.nats.io/CVE/secnote-2026-10.txtMitigationVendor Advisory
- https://github.com/nats-io/nats-server/security/advisories/GHSA-vprv-35vv-q339MitigationVendor Advisory
FAQ
What is CVE-2026-33218?
CVE-2026-33218 is a vulnerability with a CVSS score of 7.5 (HIGH). 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...
How severe is CVE-2026-33218?
CVE-2026-33218 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-33218?
Check the references section above for vendor advisories and patch information. Affected products include: Linuxfoundation Nats-Server.