CVE WatchJul 9, 2026

CVE-2026-58208

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 l

CVSS

6.8

Medium

EPSS

0.6%

p44

KEV

—

Exploit Today

0-100

Published: Jul 8, 2026 · Last modified: Jul 9, 2026 · CWE-248

EPSS · 30d

0.5%EPSS · 30 days0.6%

2026-07-092026-07-17

Technical description

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.

Official references

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