The attack can be launched within the Wi-Fi range, and the attack is located exactly where the hacker messenger is located. The attacker uses a computer to send a large number of "deauthorization" packets to the target cloud camera to prevent them from using the access point when they try to authenticate again. This is a well-known WiFi Jammer technology and is not specific to Cloud Cam.
https://www.dojammer.com/wireless-wifi-blockers.html