Schneier on Security

Bank ATM usually have a locked room where the back panel access is. At least in Montreal. The most common locks I've seen on those doors are either Abloy (old and new style) or Medeco.

Then there's the vendor supplied key to access the inside and *then* there's the vault's combination. Additionnaly, access is carefully logged, video cameras film everything and the ATM independently transfers a transaction log to the processing center receiving the content of the vault. I don't know if it independently reports the content of the bill cassettes however, but the transaction log should account balance out with the cash deliveries.

The keypads are supposed to be tamper-resistant and perform the the PIN encryption independently of the ATM O/S. The whole thing is a sealed unit which should disable itself on tampering. Likewise a cryptocard (like IBM's) is used to encrypt the backhaul link. Keying was traditionally down with a pair of sub-keys at least one of which is entered by a separate individual, usually from security.

However, I haven't worked in a bank for a little while now. Things may have changed/evolved a bit.

If voting machines were treated like bank ATMs, risk would be quite low indeed. Instead even the little in-store mini-ATM get better treatment then voting machines. With things like mandatory security cam laws and reasonnable locks.