CVE-2026-58211 — NATS Server: `no_auth_user` pre-CONNECT fast path bypasses user connection restrictions
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_…
Published: 2026-07-08 · CVSS: 5.4 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7