CVE-2026-58211 (GCVE-0-2026-58211)

Vulnerability from cvelistv5 – Published: 2026-07-08 20:16 – Updated: 2026-07-09 14:27
VLAI
Title
NATS Server: `no_auth_user` pre-CONNECT fast path bypasses user connection restrictions
Summary
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.
Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-09 14:27 UTC
CWE
  • CWE-863 - Incorrect Authorization
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8035 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
nats-io nats-server Affected: < 2.12.12
Affected: >= 2.14.0-RC.1, < 2.14.3
guessed Create a notification for this product.
Show details on NVD website
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