‫So in the previous lecture, we couldn't crack the password of the user.
‫Cyber Lab.
‫So let's try to crack it with the brute force attack.
‫Brute force attack means a lot of time because it tries all the possibility.
‫So if you choose the correct character, set the success rate of cracking a password by brute force
‫attack is theoretically 100 percent.
‫But how long will it take if the password length is more than eight?
‫It will take months, years or thousands of years to try all the password possibilities for any ordinary
‫computer.
‫So as you see in the table, the LM password is not empty for Cyber Lab.
‫A tip here.
‫The hash of an empty password starts with a D and ends with four e.
‫Look at the LM hash of the guest user, split the hash into two identical parts.
‫You'll see two hashes that start with add and end with four each.
‫As I mentioned before, the method splits the password into two seven character passwords and then takes
‫the hash, which means we have to crack to seven character passwords.
‫Well, fair enough.
‫L.A. Method converts the password to all caps, so the character set is not so big.
‫We can crack an LM hash in an acceptable time interval.
‫So right click on the Cyber Lab line and brute force attack, select Elon hashes.
‫The brute force attack window is a bit different from the dictionary attack window and, as expected,
‫no dictionary list now.
‫Instead, we have a character set combo box.
‫The default character set are just uppercase letters and numbers.
‫No alphanumeric characters in the set.
‫So to keep the demo fast, let's just go with this set.
‫It says to two hashes loaded and as you know, the hash value is split into two identical parts.
‫On the upper right hand corner, we can choose the minimum and the maximum length of the passwords for
‫Method Max, maxlength for the password is seven.
‫So this configuration is perfect.
‫Now, I pressed the Start button to start the attack.
‫Wow.
‫It found the value of one of the hashes in milliseconds.
‫So let's look at the hash file.
‫Yeah, it's the second part.
‫So that means that the password ends with cue.
‫I think the password of the Cyber Lab user is the same with the passwords of the administrator except
‫the dot at the end.
‫But we'll see.
‫So let's look at the key rate.
‫Cain tries more than 10 million passwords in a second.
‫Now that's pretty fast.
‫In the time left frame, we can see that the trying all possible passwords will take about two hours
‫unless Cain cracks it.
‫So let the Cain run for a while.
‫All right, and we're back.
‫It took more than an hour, and here's the result.
‫We're lucky because no alphanumeric character is in the password and we succeeded to crack it.
‫The first part is one, two, three four QQQ.