CVE-2026-58213
NATS Server: MQTT SUBSCRIBE Protocol Injection via Leaf Node/Route Forwarding allows arbitrary NATS command injection
- State
- Published
- Severity
- 7.1 High
- Published
- Jul 8, 2026
- Updated
- Jul 9, 2026
- Reserved
- Jun 29, 2026
Description
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.1 and 2.12.9, an MQTT client could include protocol control characters in subscription filters that were later forwarded as NATS protocol data to route or leafnode connections, corrupting the forwarded protocol stream and allowing injection of unintended NATS protocol operations. This issue is fixed in versions 2.14.1 and 2.12.9.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.1 High | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N | GitHub_M |
Weaknesses
- CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Affected Products
| Product | Versions |
|---|---|
nats-servernats-io |
|
References
- https://github.com/nats-io/nats-server/security/advisories/GHSA-qrcv-3558-gj4f
- https://github.com/nats-io/nats-server/pull/8163
- https://github.com/nats-io/nats-server/pull/8164
- https://github.com/nats-io/nats-server/commit/366837cfc65ab9ccb4f98193c65e8daf238582d8
- https://github.com/nats-io/nats-server/commit/64ebae40051ee497c481e10f316238faf0de1736
- https://github.com/nats-io/nats-server/commit/f14856b9e57a36818f43851cb69b6e33670885c9
- https://github.com/nats-io/nats-server/releases/tag/v2.12.9
- https://github.com/nats-io/nats-server/releases/tag/v2.14.1
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