CVE-2026-33216
highpriority · track · 30EPSS 0.004 · 31 %ileDEEUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–8.6
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (14)
Products and version ranges known to be affected.
- linuxfoundation nats-server2.12.0 → 2.12.6nvdUScpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*
- Go github.com/nats-io/nats-server/v22.12.0-RC.1 → 2.12.6osvUSpkg:golang/github.com/nats-io/nats-server/v2
advisories (4)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-0858NATS Server: Mehrere SchwachstellenDeutsch2026-03-24csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in NATS Server ausnutzen, um Informationen offenzulegen oder zu manipulieren, einen Denial-of-Service zu verursachen und Sicherheitsmechanismen zu umgehen.
- GHSA-v722-jcv5-w7mcNATS has MQTT plaintext password disclosure2026-03-24ghsa · osvUS
### Background NATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing. The nats-server provides an MQTT client interface. ### Problem Description For MQTT deployments using usercodes/passwords: MQTT passwords are incorrectly classified as a non-authenticating identity statement (JWT) and exposed via monitoring endpoints. ### Affected Versions Any version before v2.12.6 or v2.11.15 ### Workarounds Ensure monitoring end-points are adequately secured. Best practice remains to not expose the monitoring endpoint to the Internet or other untrusted network users.
- BIT-nats-2026-33216NATS has MQTT plaintext password disclosure2026-03-27vendor · osvUS
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.
- GO-2026-4836NATS has MQTT plaintext password disclosure in github.com/nats-io/nats-server2026-03-26vendor · osvUS
NATS has MQTT plaintext password disclosure in github.com/nats-io/nats-server
also known as (6)
Other names and identifiers for this entity.
- CNNVD-202603-4881cnnvd
- EUVD-2026-15964enisa_euvd
- GHSA-v722-jcv5-w7mcenisa_euvd
- BIT-nats-2026-33216osv
- GHSA-v722-jcv5-w7mcosv
- GO-2026-4836osv
sources
Which sources assert this record, and when.
references (17)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2026-33216cnnvd
- https://advisories.nats.io/CVE/secnote-2026-05.txtcnnvd
- https://github.com/nats-io/nats-server/commit/b5b63cfc35a57075e09c1f57503d31721bed8099cnnvd
- https://github.com/nats-io/nats-server/releases/tag/v2.12.6Patchcnnvd
- https://github.com/nats-io/nats-server/security/advisories/GHSA-v722-jcv5-w7mccnnvd
- https://advisories.nats.io/CVE/secnote-2026-05.txtenisa_euvd
- https://github.com/nats-io/nats-server/commit/b5b63cfc35a57075e09c1f57503d31721bed8099enisa_euvd
- https://github.com/nats-io/nats-server/security/advisories/GHSA-v722-jcv5-w7mcenisa_euvd
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