Medium severity · published Mar 25, 2026
CVE-2026-33247
NATS credentials are exposed in monitoring port via command-line argv
5.3
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 37% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NA
nats-server · nats-io
< 2.11.15; >= 2.12.0-RC.1, < 2.12.6 · source: vendor, NVD
MG
Multicluster Global Hub 1.4.5 · Red Hat
All versions, or not specified · source: CISA
MG
Multicluster Global Hub 1.6.5 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat multicluster global hub 1.5.3 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33247
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33247
Mitigation
https://advisories.nats.io/CVE/secnote-2026-14.txt
Mitigation
https://github.com/nats-io/nats-server/security/advisories/GHSA-x6g4-f6q3-fqvv
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:21769
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:22347
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:23345
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-33247
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