Mosquitto is an open source implementation of a server for version 3.1 and 3.1.1 of the MQTT protocol.
Affected versions of this package are vulnerable to NULL Pointer Dereference. If an authenticated client that had connected with
MQTT v5 sent a crafted
CONNACK message to the broker, a NULL pointer dereference would occur.
Mosquitto to version 2.0.10 or higher.