CVE-2026-33218

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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://advisories.nats.io/CVE/secnote-2026-10.txt	Mitigation Vendor Advisory
https://github.com/nats-io/nats-server/security/advisories/GHSA-vprv-35vv-q339	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:linuxfoundation:nats-server::::::::
	cpe:2.3:a:linuxfoundation:nats-server::::::::

History

No history.

Information

Published : 2026-03-25 20:16

Updated : 2026-03-26 17:15

NVD link : CVE-2026-33218

Mitre link : CVE-2026-33218

CVE.ORG link : CVE-2026-33218

JSON object : View

Products Affected

linuxfoundation

nats-server

CWE

CWE-20

Improper Input Validation

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