What Is THC Hydra? Basic Overview

Hydra or THC Hydra is a popular and respected network logon cracker (password cracking tool) that can support many different services.

I interviewed the developer of THC Hydra!

If you’d like to see other tools then I’d suggest you visit our Password Hacking Resource here.

For more general specific information on Hacking Tools then be sure to visit that resource where I list the best and most commonly used password crackers, IP Scanners, Wireless Hacking Tools and more! Each of the tools contains a video tutorial.


How does Hydra work?

Hydra is a brute force password cracking tool. In information security (IT security), password cracking is the methodology of guessing passwords from databases that have been stored in or are in transit within a computer system or network.

A common approach and the approach used by Hydra and many other similar pentesting tools and programs are referred to as Brute Force. I plan to write a ‘Brute Force Hacking’ post in 2024 but since this post is all about Hydra let’s place the brute-force attack concept within this password-guessing tool.

Brute force just means that the program launches a relentless barrage of passwords at login to guess the password. As we know, the majority of users have weak passwords and all too often they are easily guessed. A little bit of social engineering and the chances of finding the correct password for a user are multiplied.

Most people (especially those non-IT savvy, will base their ‘secret’ passwords on words and nouns that they will not easily forget. These words are common: loved ones, children’s names, street addresses, favorite football team, place of birth, etc.

All of this is easily obtained through social media so as soon as the hacker has compiled this data it can be compiled within a ‘password list’.

Brute force will take the list that the hacker built and will likely combine it with other known (easy passwords, such as ‘password1, password2’ etc) and begin the attack.

Depending on the processing speed of the hackers (auditors) computer, Internet connection (and perhaps proxies) the brute force methodology will systematically go through each password until the correct one is discovered.

It is not considered as being very subtle – but hey it works!

Hydra is considered as being one of the better ones out there and it certainly worth your time as a security professional or student to give it a try.

Resources And Tutorials

The majority of pentesting/ hacking tools are created and developed from a security perspective, meaning that they are designed to aid the pentester find flaws in their clients’ systems and take appropriate action.

Hydra works by helping the auditor find weak passwords in their clients’ network. According to the Hydra developers they recommend that the professional do the following when using Hydra:

  • Step 1: Make your network as secure as possible.
  • Step 2: Set up a test network
  • Step 3: Set up a test server
  • Step 4: Configure services
  • Step 5: Configure the ACL
  • Step 6: Choose good passwords
  • Step 7: Use SSL
  • Step 8: Use Cryptography
  • Step 9: Use an IDS
  • Step 10: Throw Hydra against the security and try and crack the logon commands.

How do we defend against Hydra and brute force attacks?

There are several ways a system admin or network engineer can defend against brute force attacks. Here are a few methods. If you can think of any others or disagree with the below, let us know in the comment below!

Disable or block access to accounts when a predetermined number of failed authentication attempts has been reached.

  • Consider multi-factor or double opt-in/ log in for users.
  • Consider implementing hardware-based security tokens in place of system-level passwords.

Enforce all employees to use generated passwords or phrases and ensure every employee uses symbols whenever possible.

And the most simple – remove extremely sensitive data from the network, isolate it!

In Summary

What are your thoughts? Have you used Hydra in any white/ back box pentesting and did it work or fail?

Can you think of any particular uses with this program or are there alternatives that we should also share with your community?

Henry "HMFIC"

I'm Henry, the guy behind this site. I've been Growth Hacking since 2002, yep, that long...

26 thoughts on “What Is THC Hydra? Basic Overview

  1. Open proxies are often used by ISPs and firms to decrease network loads. For those running old version, browser upgrading is important. This eliminates the chance of a hacker gaining control of your information while you are online.

      1. I still cannot get Hydra GUI up and running, all I get is a lot of files full of code, I have tried both windows & Linux downloads as well as downloads for Cygwin on Windows, also tried download from Github.

  2. Actually, you don’t need a list to do a hack. You can just use “-x” instead of “-P”. “-P” tells Hydra you’ll load passwords from a list. “-x” tells it that you’ll want it to guess the pass word. but the full command would be something like this: -x 6:8:a. 6 representing the minimum number of characters. 8 representing the maximum number of characters and “a” representing the letter you wish to start with. Have fun!

  3. Dose anyone know the simplest way to hack wifi by scripting with hydra? need some help. for presentation .

  4. The most likely abuser is just a spammer looking for emails to use in a botnet, therefore website content should be updated on regular basis, time interval varies on the type of industry you deal in. One crude yet highly successful method of slowing networks and taking websites down is the DOS (denial of service) attack.

  5. i want to get password “aashik123” i just knew there is five digits letters and remaining 3 digits numbers. can you write crunch for me dude

  6. Hi Asiq – the short answer is that I’m not too sure. I’d suggest that you contact the local consulate or US Embassy. Attending a conference would be a non-employment based event so I think it ought to be pretty straight forward. Good luck and let us know how you get on.

  7. I got in trouble at school, and now a teacher has to log on for me, and I AM NOT ALLOWED TO KNOW MY OWN PASSWORD! So I am trying to find something to guess the password. Do you have any recommendations?

  8. Well, a dictionary attack is a form of brute force attack. Both are similar. Dictionary attack is a subset of brute force attack.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Recent Posts