CVE-2026-58214
MEDIUM
NVD
CVSS Score
4.3
Severity
MEDIUM
Published
Jul 08, 2026
Vendor
unknown
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, 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.
References
- https://github.com/nats-io/nats-server/commit/297b166be60fe13144084eed4b25201ead03204a
- https://github.com/nats-io/nats-server/commit/34b09657bb596d5f850eaa5cfc97ea6b2f989a97
- https://github.com/nats-io/nats-server/releases/tag/v2.12.12
- https://github.com/nats-io/nats-server/releases/tag/v2.14.3
- https://github.com/nats-io/nats-server/security/advisories/GHSA-4g68-3pwx-5vfj