GHSA-3f24-pcvm-5jqc

Source

https://github.com/advisories/GHSA-3f24-pcvm-5jqc

Import Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-3f24-pcvm-5jqc/GHSA-3f24-pcvm-5jqc.json

JSON Data

https://api.osv.dev/v1/vulns/GHSA-3f24-pcvm-5jqc

Aliases

Downstream

MINI-f3qw-574r-82r8

Related

CGA-mvv8-7788-xf2r

Published

2026-03-24T21:51:08Z

Modified

2026-03-27T22:16:25.848943Z

Severity

4.2 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N CVSS Calculator

Summary

NATS has mTLS verify_and_map authentication bypass via incorrect Subject DN matching

Details

Background

NATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing.

One authentication model supported is mTLS, deriving the NATS client identity from properties of the TLS Client Certificate.

Problem Description

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.

Affected Versions

Fixed in nats-server 2.12.6 & 2.11.15

Workarounds

Developers should review their CA issuing practices.

Database specific

{
    "github_reviewed": true,
    "cwe_ids": [
        "CWE-287",
        "CWE-295"
    ],
    "nvd_published_at": "2026-03-25T21:16:47Z",
    "github_reviewed_at": "2026-03-24T21:51:08Z",
    "severity": "MODERATE"
}

References

Affected packages

Go / github.com/nats-io/nats-server/v2

Package

Name: github.com/nats-io/nats-server/v2; View open source insights on deps.dev
Purl: pkg:golang/github.com/nats-io/nats-server/v2

Affected ranges

Type: SEMVER
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

2.11.15

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-3f24-pcvm-5jqc/GHSA-3f24-pcvm-5jqc.json"

Go / github.com/nats-io/nats-server/v2

Package

Name: github.com/nats-io/nats-server/v2; View open source insights on deps.dev
Purl: pkg:golang/github.com/nats-io/nats-server/v2

Affected ranges

Type: SEMVER
Events: Introduced

2.12.0-RC.1

Fixed

2.12.6

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-3f24-pcvm-5jqc/GHSA-3f24-pcvm-5jqc.json"

Go / github.com/nats-io/nats-server

Package

Name: github.com/nats-io/nats-server; View open source insights on deps.dev
Purl: pkg:golang/github.com/nats-io/nats-server

Affected ranges

Type: SEMVER
Events: Introduced

0Unknown introduced version / All previous versions are affected

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-3f24-pcvm-5jqc/GHSA-3f24-pcvm-5jqc.json"