PT-2026-56582 · Nats.Io · Nats Server

Published 2026-07-08 · Updated 2026-07-08 · CVE-2026-58208

NVD

CVSS v3.1

6.8

Medium

Base vector

AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H

NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.

Fix

Weakness Enumeration

CWE-248

Related Identifiers

CVE-2026-58208

Affected Products

Nats Server

References · 6

• https://nvd.nist.gov/vuln/detail/CVE-2026-58208 · Security Note
• https://github.com/nats-io/nats-server/releases/tag/v2.14.3 · Note
• https://github.com/nats-io/nats-server/commit/73b3dd9a5ea0fa7bf08b702338676355b29b5fb4 · Note
• https://github.com/nats-io/nats-server/releases/tag/v2.12.12 · Note
• https://github.com/nats-io/nats-server/commit/837536b98b3a9280b993282155ff2bdd3ca38c30 · Note
• https://github.com/nats-io/nats-server/security/advisories/GHSA-p957-7v2w-g93g · Note