NATS has MQTT plaintext password disclosure
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.
describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2026-33216US | high7.5 | — | ||
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… | ||||
references
External citations — patches, advisories, analysis.
- https://access.redhat.com/errata/RHSA-2026:21769WEB
- https://access.redhat.com/errata/RHSA-2026:22347WEB
- https://access.redhat.com/errata/RHSA-2026:23345WEB
- https://access.redhat.com/security/cve/CVE-2026-33216WEB
- https://advisories.nats.io/CVE/secnote-2026-05.txtADVISORY
- https://bugzilla.redhat.com/show_bug.cgi?id=2451448WEB
- https://github.com/nats-io/nats-server/commit/b5b63cfc35a57075e09c1f57503d31721bed8099FIX
- https://github.com/nats-io/nats-server/security/advisories/GHSA-v722-jcv5-w7mcADVISORY
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