CVE-2026-33356

high

Description

In Meari IoT Cloud MQTT Broker deployments running EMQX 4.x, any authenticated low-privilege account can subscribe to global wildcard topics and receive telemetry from devices the user does not own. The broker enforces publish restrictions but does not enforce equivalent subscribe authorization at per-device scope.

References

https://www.runzero.com/advisories/meari-mqtt-broker-missing-per-device-subscribe-acl-cve-2026-33356/

https://github.com/xn0tsa/nobody-puts-baby-in-a-corner

Details

Source: Mitre, NVD

Published: 2026-05-11

Updated: 2026-05-13

Risk Information

CVSS v2

Base Score: 6.8

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

Severity: Medium

CVSS v3

Base Score: 7.7

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

Severity: High

EPSS

EPSS: 0.00028