# CVE-2023-47090: nats-server: NATS nats-server before 2.9.23 and 2.10.x before 2.10.2 has an authentication bypass

CVE-2023-47090 is fixed in nats-server on 1 platform, first by DEBIAN-CVE-2023-47090, released October 30, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2023-47090
- Priority: Routine
- CVSS: 6.5 (medium)
- EPSS: 0.0083
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 30, 2023

## Description

NATS nats-server before 2.9.23 and 2.10.x before 2.10.2 has an authentication bypass. An implicit $G user in an authorization block can sometimes be used for unauthenticated access, even when the intention of the configuration was for each user to have an account. The earliest affected version is 2.2.0.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | nats-server Debian 13.5 (trixie) | 2.10.3-1 | [DEBIAN-CVE-2023-47090](https://patchblox.com/security/data/fix/linux/debian-cve-2023-47090.md) | Oct 30, 2023 |
| Linux | nats-server Debian 14 | 2.10.3-1 | [DEBIAN-CVE-2023-47090](https://patchblox.com/security/data/fix/linux/debian-cve-2023-47090.md) | Oct 30, 2023 |

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Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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