CVE-2026-58210highCWE-400

CVE-2026-58210: high-severity vulnerability in nats-io nats-server

NATS Server: MQTT partial CONNECT packets can exhaust pre-auth memory

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 0.7%
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, an unauthenticated MQTT client could cause the server to retain large incomplete MQTT CONNECT packets before authentication completed, consuming server memory while the parser waited for the advertised MQTT packet length. This issue is fixed in versions 2.14.3 and 2.12.12.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
nats-io · nats-server
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