Help make a mask or rule

[question]

Passwords are only 15 characters long. This is generated passwords!!!
Example:
2SDbmEXiTQF886P
6SQzR86RfngQ9F2
CAx3JTXmUdBJ93W

small + large + numbers
a-z
A-Z
0-9

How to create a mask or a rule for these passwords?

[drsnooker]

15 chars will take years if not centuries to crack!
If you're willing to wait that long, or have access to the enterprise's computer:
-a 3 -1 ?u?l?d ?1?1?1?1?1?1?1?1?1?1?1?1?1?1?1

Actually think you'll probably get an error as the password is too long. Eventually (years from now, when we all have access to the enterprise's computer) the limit will have to be extended.

Depending on your desperation, you might want to reverse engineer the password generator app.