CVE-2026-33218 (GCVE-0-2026-33218)

Vulnerability from cvelistv5 – Published: 2026-03-25 19:53 – Updated: 2026-06-30 12:07
VLAI
Title
NATS has pre-auth server panic via leafnode handling
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-20 - Improper Input Validation
  • CWE-1286 - Improper Validation of Syntactic Correctness of Input
Assigner
References
Impacted products
Vendor Product Version
nats-io nats-server Affected: < < 2.11.15
Affected: >= 2.12.0-RC.1, < 2.12.6
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Red Hat Multicluster Global Hub 1.4.5     cpe:/a:redhat:multicluster_globalhub:1.4::el9
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Red Hat Multicluster Global Hub 1.5.4     cpe:/a:redhat:multicluster_globalhub:1.5::el9
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Red Hat Multicluster Global Hub 1.6.2     cpe:/a:redhat:multicluster_globalhub:1.6::el9
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Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
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