CVE-2026-33215
Description
NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. The nats-server provides an MQTT client interface. Prior to versions 2.11.15 and 2.12.5, Sessions and Messages can by hijacked via MQTT Client ID malfeasance. Versions 2.11.15 and 2.12.5 patch the issue. No known workarounds are available.
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 โ if you've already worked around this in production โ publish your fix to the community-verified tier.
โ Propose a mitigation on Community โ 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
| OS | Version | Status | Fixed in |
|---|---|---|---|
| debian | bookworm | affected | |
| debian | forky | fixed | 2.12.6-1 |
| debian | sid | fixed | 2.12.6-1 |
| debian | trixie | affected | |
Package impact
| Ecosystem | Package | Vulnerable | Fixed |
|---|---|---|---|
| Go | github.com/nats-io/nats-server/v2 | <2.11.15 | 2.11.15 |
| Go | github.com/nats-io/nats-server/v2 | >=2.12.0-RC.1,<2.12.6 | 2.12.6 |
| Go | github.com/nats-io/nats-server | | |
References
- https://github.com/nats-io/nats-server/security/advisories/GHSA-fcjp-h8cc-6879
- https://nvd.nist.gov/vuln/detail/CVE-2026-33215
- https://advisories.nats.io/CVE/secnote-2026-06.tx
- https://github.com/nats-io/nats-server
- https://pkg.go.dev/vuln/GO-2026-4833
- https://security-tracker.debian.org/tracker/CVE-2026-33215
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.