CVE-2026-58211
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…
Does this matter?
Lower severity and a low EPSS score (0.29%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
- EPSS
- 0.29% probability · 22th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-863
- Affected
- linuxfoundation/nats-server
- Source
- security-advisories@github.com
References
- https://github.com/nats-io/nats-server/security/advisories/GHSA-hmmp-q8cx-v964Mitigation, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.