Most methods of password cracking require the computer to produce many candidate passwords, each of which is checked. The time to crack a password is related to bit strength ( see password strength), which is a measure of the password's entropy, and the details of how the password is stored.
On a file-by-file basis, password cracking is utilized to gain access to digital evidence to which a judge has allowed access, when a particular file's permissions are restricted. The purpose of password cracking might be to help a user recover a forgotten password (installing an entirely new password is less of a security risk, but it involves System Administration privileges), to gain unauthorized access to a system, or to act as a preventive measure whereby system administrators check for easily crackable passwords. Another type of approach is password spraying, which is often automated and occurs slowly over time in order to remain undetected, using a list of common passwords. A common approach ( brute-force attack) is to repeatedly try guesses for the password and to check them against an available cryptographic hash of the password. In cryptanalysis and computer security, password cracking is the process of recovering passwords from data that has been stored in or transmitted by a computer system in scrambled form. Recovering passwords stored or transmitted by computer systems
