CVE-2026-29785
Description
NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.14 and 2.12.5, if the nats-server has the "leafnode" configuration enabled (not default), then anyone who can connect can crash the nats-server by triggering a panic. This happens pre-authentication and requires that compression be enabled (which it is, by default, when leafnodes are used). Versions 2.11.14 and 2.12.5 contain a fix. As a workaround, disable compression on the leafnode port.
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 |
|---|---|---|---|
| sles | affected | | |
| 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 | <2.11.14 | 2.11.14 |
| Go | github.com/nats-io/nats-server/v2 | >=2.12.0-RC.1,<2.12.5 | 2.12.5 |
| Go | github.com/nats-io/nats-server | | |
References
- https://github.com/nats-io/nats-server/security/advisories/GHSA-52jh-2xxh-pwh6
- https://nvd.nist.gov/vuln/detail/CVE-2026-29785
- https://github.com/nats-io/nats-server/commit/a1488de6f2ba6e666aef0f9cce0016f7f167d6a8
- https://advisories.nats.io/CVE/secnote-2026-04.txt
- https://github.com/nats-io/nats-server
- https://www.suse.com/security/cve/CVE-2026-29785.html
- https://security-tracker.debian.org/tracker/CVE-2026-29785
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.