CVE-2026-33216 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-33216HIGH

nats-io nats-server — NATS has MQTT plaintext password disclosure

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  H  N  N    7.5   .0037   29.8     —

AFFECTED
  Product      Versions     Fixed
  nats-server  < 2.11.15 –  —

TIMELINE
  Mar 17  Reserved by GitHub_M
  Mar 25  Published (CNA: GitHub_M)
  Aug 17  RESCORED — CVE-2026-33216 (nats-io nats-server). CVSS 8.6 → 7.5 (NVD).

CWE-256 · CNA: GitHub_M · CVSS v3.1 · 9 references · NVD status: Modified

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
March 17, 2026	Reserved	Reserved by GitHub_M
March 25, 2026	Published	Published (CNA: GitHub_M)
August 17, 2026	RESCORED	RESCORED — CVE-2026-33216 (nats-io nats-server). CVSS 8.6 → 7.5 (NVD).

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
nats-io	nats-server	—	< 2.11.15	—

Weaknesses

CWE-256

References (9)

https://access.redhat.com/errata/RHSA-2026:21769 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/errata/RHSA-2026:22347 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/errata/RHSA-2026:23345 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/security/cve/CVE-2026-33216 [vdb-entry, x_refsource_REDHAT]
https://advisories.nats.io/CVE/secnote-2026-05.txt [x_refsource_MISC]
https://bugzilla.redhat.com/show_bug.cgi?id=2451448 [issue-tracking, x_refsource_REDHAT]
https://github.com/nats-io/nats-server/commit/b5b63cfc35a57075e09c1f57503d31721bed8099 [x_refsource_MISC]
https://github.com/nats-io/nats-server/security/advisories/GHSA-v722-jcv5-w7mc [x_refsource_CONFIRM]
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33216.json [x_sadp-csaf-vex]

Authoritative record: CVE-2026-33216 at cve.org

Vendors: nats-io

Weaknesses: CWE-256

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-33216 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.