Vulnerability in Linuxfoundation Nats-Server
CVE-2026-33216
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.006 (49.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 49.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.003
Affected products
- Linuxfoundation Nats-Server
- Nats-Io Nats-Server — versions < 2.11.15, >= 2.12.0-RC.1, < 2.12.6
Weakness classification (CWE)
References
- github.com/nats-io/nats-server/security/advisories/GHSA-v722-jcv5-w7mc (Mitigation, Vendor Advisory)
- github.com/nats-io/nats-server/commit/b5b63cfc35a57075e09c1f57503d31721bed8099 (Patch)
- advisories.nats.io/CVE/secnote-2026-05.txt (Mitigation, Vendor Advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-33216?
- CVE-2026-33216 is a high-severity vulnerability in Linuxfoundation Nats-Server, classified under Plaintext Storage of a Password. CVSS score: 8.6/10. Published 2026-03-25.
- How severe is CVE-2026-33216?
- High severity. CVSS v3 base score is 8.6 out of 10.