[mdip]

Combine that with the assumption that the average consumer probably used a date of some significance for their 4-digit code and in the US you can guess that 0 or 1 was first, 0, 1, 2 or 3 was the third position, leaving you only to guess the second and fourth position.

[rogerbinns]

There are only 24 possible combinations of a 4 digit code anyway (assuming 4 different digits). I doubt the devices do a lockout on the wrong code, so it wouldn't take that long to hack.

[mikesun]

uh, where'd you get 24? how about 10 X 9 X 8 X 7 = 5040 combinations.

[mappu]

>I've actually encountered keypads where the order didn't actually matter

If the order really doesn't matter, then that counts combinations twice (1234, 1243..). There are 10000 possible 4-digit codes, 5040 permutations, and actually 210 combinations.

[rogerbinns]

You haven't taken into account that by looking at the keypad you can tell which digits are actually used.

[rogerbinns]

Because from fingerprints and similar gunk on the pad you can tell which 4 digits were used.