NATS has mTLS verify_and_map authentication bypass via incorrect Subject DN matching (nats-io nats-server)

CVE-2026-33248
MEDIUM 4.2

En bref

Source
NVD
EPSS
EPSS 0.15 % · centile 4 ()
État
PUBLISHED
Publiée
Mise à jour
Attribuée par
GitHub_M
Statut NVD
Analyzed

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.

Faiblesses (CWE)

  • CWE-287 — Authentification incorrecte
  • CWE-295 — Validation incorrecte de certificat

Références

Scores

VersionScoreVecteurÉvalué par
CVSS 3.1MEDIUM 4.2CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:NGitHub_M
CVSS 3.1MEDIUM 4.2CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:NNVD · security-advisories@github.com (Secondary)

Avis

Références européennes

Configurations affectées (CPE NVD)

Produits affectés

ProduitVersions
nats-io · nats-serveraffected < 2.11.15 ; affected >= 2.12.0-RC.1, < 2.12.6

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD