CVEvulnerability

CVE-2026-33248

4.2 MEDIUM Published 2026-03-25 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-03-25
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
4.2 MEDIUM — CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
Weaknesses
CWE-287, CWE-295

Description

NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, when using mTLS for client identity, with `verify_and_map` to derive a NATS identity from the client certificate's Subject DN, certain patterns of RDN would not be correctly enforced, allowing for authentication bypass. This does require a valid certificate from a CA already trusted for client certificates, and `DN` naming patterns which the NATS maintainers consider highly unlikely. So this is an unlikely attack. Nonetheless, administrators who have been very sophisticated in their `DN` construction patterns might conceivably be impacted. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, developers should review their CA issuing practices.

Affected configurations

• linuxfoundation nats-server (< 2.11.15) • linuxfoundation nats-server (>= 2.12.0 < 2.12.6)

Related

Weakness · CWE (2)

  • CWE-287 Improper Authentication weakness
  • CWE-295 Improper Certificate Validation weakness

References