CVE-2026-58214

medium

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/security/advisories/GHSA-4g68-3pwx-5vfj

https://github.com/nats-io/nats-server/releases/tag/v2.14.3

https://github.com/nats-io/nats-server/releases/tag/v2.12.12

https://github.com/nats-io/nats-server/commit/34b09657bb596d5f850eaa5cfc97ea6b2f989a97

https://github.com/nats-io/nats-server/commit/297b166be60fe13144084eed4b25201ead03204a

Details

Source: Mitre, NVD

Published: 2026-07-08

Updated: 2026-07-13

Risk Information

CVSS v2

Base Score: 4

Vector: CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 4.3

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Severity: Medium

EPSS

EPSS: 0.00367