Medium 5.3Published Jul 8, 2026

CVE-2026-58254NATS Server: Incomplete fix for CVE-2026-33249: Leaf node connections bypass Nats-Trace-Dest permission check

Updated under an hour ago (Oct 27, 2026, 1:50 PM ET)

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It affects nats-io nats-server and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for nats-io nats-server

Exploited in the last 30 days

NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.8, message trace destination checks were applied to ordinary client connections but not consistently to messages arriving through leafnode connections, allowing a leafnode operator to send trace events to subjects that would not otherwise be permitted and to use trace-only behavior to prevent normal delivery or storage of affected messages. This issue is fixed in versions 2.14.3 and 2.12.8.

CVSS: 5.3 MEDIUM (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Weakness (CWE): CWE-863
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jul 9, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

nats-io nats-server nats_io:nats_server (from the name)	before 2.12.8; from 2.14.0-RC.1, < 2.14.3	CNA record
linuxfoundation nats-server linuxfoundation:nats-server	before 2.12.8; from 2.14.0 before 2.14.3	NVD

References

References

https://github.com/nats-io/nats-server/security/advisories/GHSA-p3j5-5hrq-p75h	x-refsource-confirm, vendor-advisory
https://github.com/nats-io/nats-server/commit/cbe845932980b71563efac5cfa4cc751c88936cd	x-refsource-misc, patch
https://github.com/nats-io/nats-server/releases/tag/v2.12.8	x-refsource-misc, release-notes
https://github.com/nats-io/nats-server/releases/tag/v2.14.3	x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.