CVE-2026-58250

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/nats-io/nats-server/commit/8dcb26eaea78fdcbe96dbee5986d6019fd5cb94a	Patch
https://github.com/nats-io/nats-server/commit/fc5fe39177533e9dbdd651d2458285bfae1dde27	Patch
https://github.com/nats-io/nats-server/releases/tag/v2.11.17	Release Notes
https://github.com/nats-io/nats-server/releases/tag/v2.12.8	Release Notes
https://github.com/nats-io/nats-server/security/advisories/GHSA-3g5q-cfh2-cq67	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:linuxfoundation:nats-server::::::::
	cpe:2.3:a:linuxfoundation:nats-server::::::::

History

25 Oct 2026, 17:10

Type	Values Removed	Values Added
Summary		(es) NATS Server es un servidor de alto rendimiento para NATS.io, el sistema de mensajería nativo de la nube y del borde. Antes de las versiones 2.12.8 y 2.11.17, un par no autenticado con acceso de red a un oyente de nodo hoja con compresión habilitada podría bloquear el servidor durante el handshake de nodo hoja previo a la autenticación al enviar mensajes de protocolo INFO de nodo hoja repetidos antes de que la autenticación y la configuración de la cuenta se completaran. Este problema está solucionado en las versiones 2.12.8 y 2.11.17.

Information

Published : 2026-07-08 20:16

Updated : 2026-10-25 17:10

NVD link : CVE-2026-58250

Mitre link : CVE-2026-58250

CVE.ORG link : CVE-2026-58250

JSON object : View

Products Affected

linuxfoundation

nats-server

CWE

CWE-476

NULL Pointer Dereference

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