CVE-2026-58208
Description
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
Debian Mixed 4 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Affected | — |
| sid | Fixed | 2.14.3-1 |
| forky | Fixed | 2.14.3-1 |
| bookworm | Affected | — |
References
- https://security-tracker.debian.org/tracker/CVE-2026-58208
- https://github.com/nats-io/nats-server/commit/73b3dd9a5ea0fa7bf08b702338676355b29b5fb4
- https://github.com/nats-io/nats-server/commit/837536b98b3a9280b993282155ff2bdd3ca38c30
- https://github.com/nats-io/nats-server/releases/tag/v2.12.12
- https://github.com/nats-io/nats-server/releases/tag/v2.14.3
- https://github.com/nats-io/nats-server/security/advisories/GHSA-p957-7v2w-g93g
CWEs
CWE-248
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.