CVE-2026-58250 | NATS Server is a high-performance server for NATS.io, the cl… | CVSS 7.5 HIGH

Description

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.

Metadata

CVE ID: CVE-2026-58250
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-06-29 21:54 UTC
Published: 2026-07-08 19:48 UTC
Last updated: 2026-07-08 19:48 UTC
Primary CWE: CWE-476
CWE-476: NULL Pointer Dereference
Vendor / Product: nats-io / nats-server
Sources: cve.org · NVD

Severity & Metrics

7.5 HIGH CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products (1)

Vendor	Product	Platform	Versions
nats-io	nats-server	—	< 2.11.17, >= 2.12.0-preview.1, < 2.12.8

Weakness (CWE)

CWE	Source	Description
CWE-476	cna	CWE-476: NULL Pointer Dereference

CVSS scores (1)

Score	Severity	Version	Source	Vector
7.5	HIGH	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References (5)

https://github.com/nats-io/nats-server/security/advisories/GHSA-3g5q-cfh2-cq67 https://github.com/nats-io/nats-server/security/advisories/GHSA-3g5q-cfh2-cq67
https://github.com/nats-io/nats-server/commit/8dcb26eaea78fdcbe96dbee5986d6019fd5cb94a 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/commit/fc5fe39177533e9dbdd651d2458285bfae1dde27
https://github.com/nats-io/nats-server/releases/tag/v2.11.17 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/releases/tag/v2.12.8