Improper Input Validation Affecting nats-server package, versions <2.12.6-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.62% (45th percentile)

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  • Snyk IDSNYK-MINIMOSLATEST-NATSSERVER-19154806
  • published21 Aug 2026
  • disclosed25 Mar 2026

Introduced: 25 Mar 2026

CVE-2026-33218  (opens in a new tab)
CWE-20  (opens in a new tab)

How to fix?

Upgrade Minimos:latest nats-server to version 2.12.6-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream nats-server package and not the nats-server package as distributed by Minimos. See How to fix? for Minimos:latest relevant fixed versions and status.

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 Base Scores

version 3.1