The local MQTT broker does not enforce topic-level Access Control Lists (ACLs). This allows any client to subscribe using wildcard characters (# or +) to enumerate hidden network devices or publish rogue control commands.
Exploitability
AV:NAC:LAT:NPR:HUI:NVulnerable System
VC:HVI:HVA:HSubsequent System
SC:NSI:NSA:N8.6/CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NAuthentication