CVE-2026-58214

Summary

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 authenticated MQTT client could subscribe to the internal $MQTT.deliver.pubrel subject family, bypassing configured subscribe permissions and exposing MQTT QoS2 protocol metadata for sessions in the account. This issue is fixed in versions 2.14.3 and 2.12.12.

Affected Software

VendorProductVersion RangeStatus
nats-ionats-server< 2.12.12affected
nats-ionats-server>= 2.14.0-RC.1, < 2.14.3affected

Weaknesses

  • CWE-863: CWE-863: Incorrect Authorization

References