HOW TO CRACK PASSWORDS ...

Cracking OR Hacking Passwords

Password hacking is one of the hottest and most widely discussed topics in the field of
computer hacking. In today’s world, passwords alone play a key role in deciding the
security of a web server or any other computer system. As a result, hacking the password
is one of the easiest and sometimes the only way to gain access to the system. In this
chapter, you will be introduced to various password hacking techniques that are frequently
used in the hacking industry.

To begin with, I will let you know some of the obvious, simple yet effective techniques to
hack passwords:

1. Social Engineering: This type of technique involves psychological manipulation of
people into performing actions that lead to the disclosure of their confidential
information. In other words, social engineering is just a trick played by the hacker to
gain the trust of people so that they reveal the password by themselves.

Scenario-1: The hacker may call the target person by pretending himself as a bank
official and ask him to confirm his password stating that this has to be done as a part
of an ongoing verification program. In most cases, the target person on the other end
believes this and reveals his password to the hacker.

Scenario-2: In order to avoid suspicion, instead of directly asking the victim to
reveal the password, the hacker may obtain other vital information such as the “Date
of Birth”, “Place of Birth”, “High School Details” etc. from the target person. Using
these details, the hacker can easily reset the password and gain unauthorized access.
Even though social engineering seems simple, it is proven that most people
would easily fall victim to this attack. Lack of awareness among people is the
prime reason for the success behind this trick.

2. Guessing: As most people are known to use easy to remember words such as their
“pet’s name”, “phone number”, “child’s name” etc. as their passwords, it is often
possible for the hacker to easily guess the password.

3. Shoulder surfing: It is the act of spying on one’s keyboard from behind the
shoulders as a person types his/her password. This technique works well particularly
in crowded areas such as cyber cafes and ATMs where people are usually unaware of
what is happening behind their shoulders.

After understanding some of the simple password hacking techniques, it is time to move
on to the next level. Now, let us jump into some of the serious methods that hackers use to
crack passwords:

DICTIONARY ATTACK

A dictionary attack is a type of password cracking technique where a long list of words
from the dictionary is repeatedly tried against the target until the right match is found. This
technique can be used to crack passwords that contain words found in the dictionary.
Generally, the success of a dictionary attack is based on the fact that most people have a
tendency to use easy to remember passwords that are found in the dictionary. However, if
one uses a strong password with a combination of alphabets and numbers or introducing a
slight variation to the actual spelling would make it impossible for the dictionary attack to
crack such passwords.

One of my favourite tool to carry out the dictionary attack is Brutus. It is a remote online
password cracker that works on Windows platform and can be downloaded from the
following link:
Brutus Download: http://www.hoobie.net/brutus/
NOTE: Some antivirus programs are known to have conflict with the Brutus application.
So, it is recommend that you temporarily disable your antivirus before running the Brutus
application.

Now,how to use Brutus. Here is a step-by-step
procedure:

1. After downloading the tool from the above link, unzip the package into a new empty
folder.
2. Run the “BrutusA2.exe” file to open the application
3. Enter the IP address (or domain name) of the target server in the “Target” field
Select the type of password that you want to crack from the “Type” field or enter
your own custom port number in the “Port” field”.
4. If you know the username for which you want hack the password for, then check the
“Single User” option and enter the username in the “UserID” field. Otherwise leave
the default settings to work as it is so that the username list is loaded from the
“users.txt” file.
5. In the “Pass Mode” field select the option “Word List”. The list of words will be
loaded from the “words.txt” file by default which contains around 800+ words. If
you’ve a .TXT file that contains more words, then you can use that by selecting the
“Browse” option. The more bigger the list is, better the chances of cracking the
password.
6. Now, hit the “Start” button to begin the cracking process. Brutus will try every word
in the password list for each of the usernames present in the username list. It will
take a while for the process to complete and if you’re lucky, you should get a positive
authentication response and the cracked password .

NOTE: It is always a smart idea to use a proxy before attempting this hacking process.
This will prevent your real IP address from being stored in the logs of remote server and
thus reduces the chances of being traced back.

BRUTE-FORCE ATTACK

Unlike the dictionary attack which tries only those words present in the list, the brute
force attack on the other hand tries every possible permutation of alphabets, numbers and
even special characters until the right password if found.
In theory, it is possible to crack any password using this approach, but here’s the catch!
Brute force attack takes a long time to crack passwords. The time actually depends on the
speed of the computer and the complexity of the password.
For example, if the target password is small and doesn’t contain any numbers or special
characters, it is fairly easy to crack such passwords using this approach. However, if the
password is lengthy, contains numbers or even special characters, this approach may take
a long time to complete. For some complex passwords, brute force approach may take up
even years to finish the cracking process as there are billions of permutations to try.

Here is how you can configure the Brutus program to try the brute force approach:

1. Configure the “Target”, “Type” and “Port” in the same way as in case of the
dictionary attack. Under the “Authentication Options”, select the “Pass Mode” as
Brute Force and click on the “Range” button
2. Once you click on “Range” you will see a number of options to select with such as
“Digits only”, “Lowercase Alpha”, “Uppercase Alpha” and so on. You can also set
the Min Length and Max Length to narrow your brute force attack options
3. Once your range selection is over, click “OK” and hit the “Start” button. The brute
force cracking attempt will begin and will take anywhere from a few minutes to a
couple of hours to complete. If the crack attempt is successful, you should see the
username and its corresponding password displayed on the Brutus window!

RAINBOW TABLE

A rainbow table is a pre-computed table that contains a long list of password hashes for
dictionary words as well as alphanumeric permutation of words. The hacker initially
generates a long list of password hashes and stores them in a rainbow table for later use.
Although generating a rainbow table initially takes a long time and utilizes more storage
space, once computed it can greatly reduce the time taken for the password cracking
process.

Any computer system that requires password authentication will maintain a table of
usernames and passwords in its database. In case if the hacker manages to steal this table
from the database, he would easily be in a position to gain access to a large number of
accounts on the target system. In order to prevent this from happening, most systems store
the passwords in a cryptographic hash format as opposed to plain text.
For example, when a user completes the sign-up process on an online portal, the system
may convert his password to MD5 hash format and store it in its database table. Suppose if
the user has his password as goldfish, its MD5 hash would be as follows:
MD5 Hash: 861836f13e3d627dfa375bdb8389214e
Thereafter whenever the user tries to log into the portal, his password gets converted to the
MD5 hash format on the fly and is compared against the existing hash in the database
table. If both the hashes match, access is granted to the user.
Now, even if the hacker manages to gain access to the database and steal the password
table, he would only see a long list of cryptographic hashes and not the actual password.
This is where rainbow tables come in handy. The hacker can use the rainbow tables to
compare the long list of pre-computed hashes against the stolen list of password hashes. If
the hashes match, the password would be the one that was initially used to generate the
hash.
Unlike a brute force approach where the hash is computed on every attempt, the rainbow
table approach on the other hand utilizes a pre-computed list of hashes to directly compare
them against an existing password hash. As the time required to compute the hash on
every attempt is cut down, the rainbow table approach takes significantly less time to
complete the cracking process.
A practical example of rainbow table approach will be discussed in the next chapter where
we take up the topic of cracking Windows passwords.

PHISHING ATTACK

Phishing is a form of social engineering technique used by hackers to gather sensitive
information such as usernames, passwords and credit card details by posing as
a trustworthy person or organization.

Phishing scams usually sends an email message to users requesting for their personal
information, or redirects them to a website where they are required to enter their personal
information.

In most cases, a phishing email directs the victims to follow a link leading to a website
where they will have to enter their login details or other confidential information. In
reality this website is a fake one created by the hacker (often referred to as spoofed
website) which is an exact replica of the original or appears similar. When the victim
enters his/her login details on a spoofed page they are actually stolen away by the hacker.

For example, the hacker may send an email that pretends to have been appearing from the
bank where the victim maintains an account and ask him/her to update the login details by
following the link present in the email. The email further mentions that this update process
is mandatory and failing to do so will result in the bank account being locked. As a
response, the victim clicks on the link where he/she will be taken to the fake login page
that looks similar to the original one. However, when the login details are entered, they are
recorded and stored on the website for later access by the hacker. The victim remains
unaware of the entire process but the hacker skilfully manages to hack the password.

IMPORTANT NOTICE – All the information provided in this blog is strictly for educational purpose only, and any illegal or unethical use of this information will not be the responsibility of the blog  .. And  as your well wisher in would say “ please use them carefully and ethically “ it will keep you out of many troubles  ..