I have a question that might sound a bit weird: A friend of mine (Person A) is being attacked by a former friend (Person B) and now person A asked me for help. Person A and Person B know each other from the internet and Person A used to trust Person B.
Generally speaking, Person A experiences network issues in his WiFi network.
Person B has access to Person A's iCloud account and other accounts. Also, Person B may have changed settings (VPN, certificates, ...) or installed apps on Person A's iPhone because Person B told Person A that he knows how to cheat in a smartphone game. Person A doesn't remember anymore what Person B told him to do. Person B never had physical access to the iPhone nor the router.
Apparently, Person B can launch an attack that stops the internet on Person A's iPhone for several minutes. This only concerns incoming traffic because during these attacks Person A can be heard by me on the call, but Person A can't hear me for the time of the attack.
This doesn't only affect the iPhone, but also other devices in the same WiFi network. That's why I was thinking that Person A might have access to the router, but he could have never had physical access.
Person A is rather inexperienced with technology and, as far as I know, Person B is an experienced senior software developer who is interested in pentesting.
Does anyone have any idea what Person B might have done to Person A's iPhone/router and how he is remotely able to stop his internet?
I appreciate any help!