Incorrect Authorization Affecting github.com/nats-io/nats-server/v2/server package, versions >=2.11.0-RC.1 <2.11.15>=2.12.0-RC.1 <2.12.6


Severity

Recommended
0.0
medium
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.23% (14th percentile)

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  • Snyk IDSNYK-GOLANG-GITHUBCOMNATSIONATSSERVERV2SERVER-15763283
  • published25 Mar 2026
  • disclosed24 Mar 2026
  • creditUnknown

Introduced: 24 Mar 2026

CVE-2026-33249  (opens in a new tab)
CWE-863  (opens in a new tab)

How to fix?

Upgrade github.com/nats-io/nats-server/v2/server to version 2.11.15, 2.12.6 or higher.

Overview

github.com/nats-io/nats-server/v2/server is an A simple, secure and performant communications system for digital systems, services and devices.

Affected versions of this package are vulnerable to Incorrect Authorization in the handling of message tracing headers. An attacker can redirect trace messages to any valid subject, including those for which they lack publish permissions, by specifying an arbitrary subject in the headers.

Notes: The payload of the trace message remains valid and is not attacker-controlled.

CVSS Base Scores

version 4.0
version 3.1