Outline
Long circulated message claims that a scammer can take control of your phone if you key in 90# (nine-zero-hash).
Brief Analysis
The information in the message is false for the great majority of domestic fixed phone systems and all mobile phones. It can be true for certain types of business phone systems that are configured in a particular way. (Scroll down for details).
Examples
FYI – Phone Scam
This has been confirmed by Telstra: DO NOT push 90# on your home phone. Got a call last night from an individual identifying himself as an AT&T Service technician who was conducting a test on our telephone lines. He stated that to complete the test I should touch nine (9), zero(0), hash (#) and then hang up. Luckily, I was suspicious and refused. Upon contacting the telephone company, I was informed that by pushing 90#, you give the requesting individual full access to your telephone line, which allows them to place long distance telephone calls billed to your home phone number. I was further informed that this scam has been originating from many of the local ails/prisons. DO NOT press 90# for ANYONE. PLEASE pass this on to your friends. If you have mailing lists and/or newsletters from organisations you are connected with, I encourage you to pass this on.
Stephen Cooper
Detective Sergeant
Major Fraud Investigation Division
[NUMBER REMOVED]
Original Source : https://www.hoax-slayer.com/nine-zero-hash-hoax.html