On 27/11/2019 22:17, Dave W wrote:
On Wed, 27 Nov 2019 18:12:30 +0000, Martin Brown
wrote:

The other thing to watch on the push button models of keysafe is that it
doesn't matter what *order* you press the buttons in so long as you only
press the right ones. This makes a 4 digit code a bit weak.

You can set a five digit code on such devices which makes it secure
enough (although not if you set a pair to 1,9).

What do you mean by "secure enough"?
The number of combinations of 4 digits is (10x9x8x7)/(4x3x2)=210.
For 5 digits it's (10x9x8x7x6)/(5x4x5x2)=252, which is hardly better.

Most of the ones I have come across are a hexadecimal 16 digit matrix.
So it is actually:

16x15x14x13/24=1820 for 4 digits
and
16x15x14x13x12/120=4368 for 5 digits

There are videos of how to crack the code in seconds by feel, but I've
tried them on a new keysafe without success. The methods probably work
if the keysafe has been in use for years with the same combination and
the grooves have been worn into sloppiness.

If it gets worn then a skilled operator can feel for the combination.

It wouldn't take too long to try all 210 combinations of 4 digit
codes, bearing in mind that it doesn't matter what order you press the
buttons.

Exactly. But the digits are chosen from 16 so it isn't quite that bad.

--
Regards,
Martin Brown