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, for MQTT deployments using usercodes/passwords: MQTT passwords are incorrectly classified as a non-authenticating identity statement (JWT) and exposed via monitoring endpoints. Versions 2.11.14 and 2.12.6 contain a fix. As a workaround, ensure monitoring end-points are adequately secured. Best practice remains to not expose the monitoring endpoint to the Internet or other untrusted network users.
Affected products
linuxfoundation: nats-server
References9
- advisories.nats.io/CVE/secnote-2026-05.txt MitigationVendor Advisory
- github.com/nats-io/nats-server/security/advisories/GHSA-v722-jc… MitigationVendor Advisory
- github.com/nats-io/nats-server/commit/b5b63cfc35a57075e09c1f575… Patch
- access.redhat.com/errata/RHSA-2026:21769
- access.redhat.com/errata/RHSA-2026:22347
- access.redhat.com/errata/RHSA-2026:23345
- access.redhat.com/security/cve/CVE-2026-33216
- bugzilla.redhat.com/show_bug.cgi?id=2451448
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33216…
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 32 · as of 12 November 2026
- CWE
- CWE-256CWE-213
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