NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a client could be registered as the configured no_auth_user through a parser path used when the first client operation was not CONNECT, bypassing user-level connection restrictions such as allowed_connection_types or proxy_required that normal authentication would apply. This issue is fixed in versions 2.14.3 and 2.12.12.
History

Fri, 10 Jul 2026 09:30:00 +0000

Type Values Removed Values Added
First Time appeared Nats
Nats nats Server
Vendors & Products Nats
Nats nats Server

Thu, 09 Jul 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 08 Jul 2026 20:45:00 +0000

Type Values Removed Values Added
Description NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a client could be registered as the configured no_auth_user through a parser path used when the first client operation was not CONNECT, bypassing user-level connection restrictions such as allowed_connection_types or proxy_required that normal authentication would apply. This issue is fixed in versions 2.14.3 and 2.12.12.
Title NATS Server: `no_auth_user` pre-CONNECT fast path bypasses user connection restrictions
Weaknesses CWE-863
References
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-07-08T20:16:25.262Z

Updated: 2026-07-09T14:27:25.118Z

Reserved: 2026-06-29T17:09:25.872Z

Link: CVE-2026-58211

cve-icon Vulnrichment

Updated: 2026-07-09T14:27:21.808Z

cve-icon NVD

No data.

cve-icon Redhat

No data.