CVE-2026-58250

EUVD-2026-42380

08.07.2026, 20:16

NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	Primary	7.5 HIGH	NETWORK	LOW	NONE	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Base Score

CVSS 3.x

EPSS Score

Percentile: 41.17%

Affected Products (NVD)

Vendor	Product	Version
linuxfoundation	nats-server	𝑥 < 2.11.17
linuxfoundation	nats-server	2.12.0 ≤ 𝑥 < 2.12.8

𝑥

= Vulnerable software versions

Debian Releases

Debian Product

Codename

nats-server

bookworm	vulnerable
forky	2.14.3-1 fixed
sid	2.14.3-1 fixed
trixie	vulnerable

Ubuntu Releases

Ubuntu Product

Codename

nats-server

jammy	dne
noble	needs-triage
questing	ignored
resolute	needs-triage

Azure Linux Releases

Azure Package

Release

telegraf

Azure Linux 3.0

0:1.31.0-24.azl3

fixed

Common Weakness Enumeration

CWE-476 - NULL Pointer Dereference
A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.

References

https://github.com/nats-io/nats-server/commit/8dcb26eaea78fdcbe96dbee5986d6019fd5cb94a

https://github.com/nats-io/nats-server/commit/fc5fe39177533e9dbdd651d2458285bfae1dde27

https://github.com/nats-io/nats-server/releases/tag/v2.11.17

https://github.com/nats-io/nats-server/releases/tag/v2.12.8

https://github.com/nats-io/nats-server/security/advisories/GHSA-3g5q-cfh2-cq67