Somebody got hold of all the details of my router (everything you can think of) and has since been able to see everything I do and type. They are also able to remotely control my computer, and control devices. I believe they may be using MAC or ARP spoofing. I ran XARP and it detected an ARP attack but I don't really understand the details. It's all guesswork at this stage. Is there any way I can stop this person doing any of this? Remote assistance is disabled. They are able to do it when I am connected via wifi or a LAN cable. Any help would be sincerely appreciated.
turn off modem for a couple of days/disconnect from internet... reset router to factory settings, properly program it with passwords that have upper/lower case numbers and characters mixed in ... Ex@^p1E instead of "example" use your imagination and make it 10-15 charceters long. the old guard will tell you use randome words like " adventure and creampie and do it like Ad^E^turE\CreAm3.1416 < - damn hard to discover.
also make sure your router has all the bios updates it should have and if it is like 10 years old change it.
make sure NAT is on, Web access to router is OFF, your SSID password is not easy to figure out and turn off WPS.
fo to advance settings, let all your stuff get on,m then secure it with MAC address lock down, unless you permit it it wont get on
then get on the internet configure it, and then see whats what.