Password Hacking Methods - Part I

Password Hacking
Password cracking is the process of recovering secret passwords from data that has been stored in or transmitted by a computer system. A common approach is to repeatedly try guesses for the password.
Most passwords can be cracked by using following techniques :

1) Hashing:- Here we will refer to the one way function (which may be either an encryption function or cryptographic hash) employed as a hash and its output as a hashed password.
If a system uses a reversible function to obscure stored passwords, exploiting that weakness can recover even 'well-chosen' passwords.
One example is the LM hash that Microsoft Windows uses by default to store user passwords that are less than 15 characters in length.
LM hash breaks the password into two 7-character fields which are then hashed separately, allowing each half to be attacked separately.



Hash functions like SHA-512, SHA-1, and MD5 are considered impossible to invert when used correctly

2) Guessing:- Many passwords can be guessed either by humans or by sophisticated cracking programs armed with dictionaries (dictionary based) and the user's personal information.
Not surprisingly, many users choose weak passwords, usually one related to themselves in some way. Repeated research over some 40 years has demonstrated that around 40% of user-chosen passwords are readily guessable by programs. Examples of insecure choices include:
* blank (none)
* the word "password", "passcode", "admin" and their derivatives
* the user's name or login name
* the name of their significant other or another person (loved one)
* their birthplace or date of birth
* a pet's name
* a dictionary word in any language
* automobile licence plate number
* a row of letters from a standard keyboard layout (eg, the qwerty keyboard -- qwerty itself, asdf, or qwertyuiop)
* a simple modification of one of the preceding, such as suffixing a digit or reversing the order of the letters.
and so on....

What people need to do, is just change the way they create their passwords.
A password containing both uppercase & lowercase characters, numbers and special characters too; is a strong password and can never be guessed.

A simple example would be:

Normal:- Xtremevirus

Better & improved:- X+r3^^3v!rU$
(But obviously don't keep your name as the password. Because it still can be guessed even if you write it in the special format.)