CVE-2017-9868
In Mosquitto through 1.4.12, mosquitto.db (aka the persistence file) is world readable, which allows local users to obtain sensitive MQTT topic information.
Date published : 2017-06-25
https://github.com/eclipse/mosquitto/issues/468
https://lists.debian.org/debian-lts-announce/2018/09/msg00036.html