It's called a backdoor because the only thing the virus does is open a connection between your computer and a third party, without your permission. The only reason this is potentially dangerous is because with viruses like a "keylogger" they, the outside party, can record each key stroke you make. However this is EVERY key stroke you make, meaning that they have to sift through all the information they have gained through logging over four thousand players key stroke history. Though ARX also has a record of your email address and can potentially gain access to it through trial and error methods of trying to enter the account using words you type often, like typing "password123" everyday you log onto your computer.
tl;dr You may lose your 12-month membership to brazzers/netflix