CVE-2026-33216
NATS has MQTT plaintext password disclosure
No known exploitation. EPSS puts it in the 51st percentile. Fixed in 2.11.15.
What to do
Find your product and version, then upgrade to the build on the right.
- Nats-io Nats-serverAffected: < 2.11.15Upgrade to: not statedAffected: >= 2.12.0-RC.1, < 2.12.6Upgrade to: not statedStated by: CVE record
- Linuxfoundation Nats-serverAffected: < 2.11.15Upgrade to: 2.11.15Stated by: NVD
Versions as the sources state them. Full version matrix after sign-in
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.7% chance of exploitation activity in the next 30 days, which ranks it in the 51st percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
36 events over 168 days, from the signal feeds we watch.
- Patch availableworkaround available, record updated
- Patch availableworkaround available, record updated
- Patch availableworkaround available, record updated
- Patch availableworkaround available, record updated
- Patch availableworkaround available, record updated
- Patch availableworkaround available, record updated
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
Scored 8.6 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity NoneNo integrity impact
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Credential AccessT1552Unsecured Credentialshigh confidence
Sources
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