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 (2)
Core 2
Core References
Technical Description technical-description
https://github.com/xn0tsa/nobody-puts-baby-in-a-corner
Third Party Advisory third-party-advisory
https://www.runzero.com/advisories/meari-mqtt-broker-missing-per-device-subscribe-acl-cve-2026-33356/
Scores
CVSS v3
7.7
EPSS
0.0027
EPSS Percentile
19.0%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-639
Status
published
Products (1)
Meari/IoT Cloud MQTT Broker EMQX
4.x
Published
May 11, 2026
Tracked Since
May 11, 2026