CVE-2026-33248 (GCVE-0-2026-33248)
Vulnerability from cvelistv5
Published
2026-03-25 20:18
Modified
2026-03-26 19:52
CWE
  • CWE-287 - Improper Authentication
  • CWE-295 - Improper Certificate Validation
Summary
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.
Impacted products
Vendor Product Version
nats-io nats-server Version: < 2.11.15
Version: >= 2.12.0-RC.1, < 2.12.6
Create a notification for this product.
Show details on NVD website


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