What’s Vulnerable › Vulnerabilities

CVE-2026-58251: NATS Server: Queue Subscribe Authz Bypass

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-08 · updated 2026-10-25
• Weakness: CWE-285

Description

NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.0, 2.12.7, and 2.11.16, an authenticated user with subscription deny permissions could bypass a plain subject deny rule by using a queue subscription, because queue-specific deny evaluation could override the plain subject deny result when the queue name itself was not denied. This issue is fixed in versions 2.14.0, 2.12.7, and 2.11.16.

Affected products

• nats-io nats-server: before 2.11.16; from 2.12.0 before 2.12.7 — fixed in 2.11.16, 2.12.7

How to fix

Upgrade to a fixed version: nats-io nats-server 2.11.16, 2.12.7. Check the vendor advisory for mitigations.

References

• https://github.com/nats-io/nats-server/commit/013586288078def45a6788096924eb4d150db65c
• https://github.com/nats-io/nats-server/commit/79c2f6e9ff87f594596337b6427dda85c38d1fe1
• https://github.com/nats-io/nats-server/commit/b9ffb63b85e7db3d25a13b2e234f5f7f7c13164d
• https://github.com/nats-io/nats-server/releases/tag/v2.11.16
• https://github.com/nats-io/nats-server/releases/tag/v2.12.7
• https://github.com/nats-io/nats-server/releases/tag/v2.14.0
• https://github.com/nats-io/nats-server/security/advisories/GHSA-jx8g-9g95-6322

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