.:: Insecure Washing Machines ::.
Disclaimer: The information provided here is for educational purposes only for those who design washing machines and external alternative payment systems. I am in no way, shape or form encouraging depriving the owners of the washing machines / dryers the money they are due for the service. Do not try this unless you own the washing machine / dryer or have valid permission to do so.
Laundry is an inevitable task that we all must take care of once a week. Most of us own a washing machine system in our houses. In buildings such as apartments and college dorms it is common to have a laundry room with large arrays of washing machines and dryers. In most laundry rooms the common method of payment is the quarter or token, however some laundry rooms accept money cards as a form of payment. This requires a separate system to perform the transaction. After the transaction is completed and verified a signal is sent to the washing machine that tells it "Hey you, the user paid us. Give them 4 tokens worth of credit." The weak point in this system is the simplicity of the protocol used to communicate with the washing machine. There are usually 3 or 4 data wires running to the washing machine, but only two of these wires are needed. Pulsing a voltage over 5V+ (but less than 30V) to one of the wires vs. the black wire (which is usually ground) tells the machine to add credits. Sounds pretty simple? Well thatís the security issue. The protocol is too simple and this is the major flaw. A lot of time the wires that go to the machine can be found sticking out of panels behind the machines and can be accessed easily. The solution? Tougher protocol and secure hard-to-access wiring.
This is a modern public washing machine that accepts external payment signals from third-party transaction devices.
This is a third-party device which charges smart card e-wallets and signals the washing machine or dryer that payment has been recieved.
A photo of poorly insulated/secured wiring dangling from a wall panel. Human error is usually the weakest point in any system and more emphasis should be placed on national electrical code.
This is a drier machine showing that necessary credits have been applied and a 60 minute cycle is due.