What is a “brute force” password cracker?
A brute force cracker simply tries all possible passwords from legal characters until it gets the password. From a cracker perspective, this is usually very time consuming. L0phtcrack 1.5, a brute force cracker, makes certain assumptions and reduces this time down considerably. As pointed out in section 03-2, the Lan Manager password concantenated to 14 bytes, and split in half. The halves can be worked on individually. If the password was originally only 7 characters or less, that second half is always 0xAAD3B435B51404EE. To further ease brute force cracking, since a substantial reduction in bits occurs during the deriving of the 8 byte DES key from the 7 byte key, less keys have to be tried. Also since the password is converted to upper case before one way encrypting it, Lan Manager password cracking does not have to take into consideration the possibility of lower case letters. L0phtcrack incorporates techniques to exploit all of these possibilities. By cracking the Lan Manager pass
A brute force cracker simply tries all possible passwords until it gets the password. From a cracker perspective, this is usually very time consuming. However, given enough time and CPU power, the password eventually gets cracked. Most modern brute force crackers allow a number of options to be specified, such as maximum password length or characters to brute force with.
