CVE-2026-33247
NATS credentials are exposed in monitoring port via command-line argv
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, if a nats-server is run with static credentials for all clients provided via argv (the command-line), then those credentials are visible to any user who can see the monitoring port, if that too is enabled. The `/debug/vars` end-point contains an unredacted copy of argv. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, configure credentials inside a configuration file instead of via argv, and do not enable the monitoring port if using secrets in argv. Best practice remains to not expose the monitoring port to the Internet, or to untrusted network sources.
How to fix CVE-2026-33247
To remediate CVE-2026-33247, upgrade the affected package to a fixed version below.
- —upgrade to 2.11.15 or later
- —no fix listed
- —no fix listed
- —upgrade to 2.11.15 or later
- —upgrade to 2.11.15 or later
Is CVE-2026-33247 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (5)
- from 0, < 2.11.15, >= 2.12.0, < 2.12.6
- from 0
- from 0
- from 0, < 2.11.15
- from 0, < 2.11.15, >= 2.12.0-RC.1, < 2.12.6
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.4 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N |