Hydra– Cyber Security 101-Offensive Security Tooling -TryHackMe Walkthrough

Learn about and use Hydra, a fast network logon cracker, to bruteforce and obtain a website’s credentials.

IritT

7 min readOct 29, 2024

Room URL: https://tryhackme.com/r/room/hydra

YouTube Video: https://www.youtube.com/watch?v=8fs_7bm88GY&t=1s

Task 1 Hydra Introduction

What is Hydra?

Hydra is a brute force online password cracking program, a quick system login password “hacking” tool.

Hydra can run through a list and “brute force” some authentication services. Imagine trying to manually guess someone’s password on a particular service (SSH, Web Application Form, FTP or SNMP) — we can use Hydra to run through a password list and speed this process up for us, determining the correct password.

According to its official repository, Hydra supports, i.e., has the ability to brute force the following protocols: “Asterisk, AFP, Cisco AAA, Cisco auth, Cisco enable, CVS, Firebird, FTP, HTTP-FORM-GET, HTTP-FORM-POST, HTTP-GET, HTTP-HEAD, HTTP-POST, HTTP-PROXY, HTTPS-FORM-GET, HTTPS-FORM-POST, HTTPS-GET, HTTPS-HEAD, HTTPS-POST, HTTP-Proxy, ICQ, IMAP, IRC, LDAP, MEMCACHED, MONGODB, MS-SQL, MYSQL, NCP, NNTP, Oracle Listener, Oracle SID, Oracle, PC-Anywhere, PCNFS, POP3, POSTGRES, Radmin, RDP, Rexec, Rlogin, Rsh, RTSP, SAP/R3, SIP, SMB, SMTP, SMTP Enum, SNMP v1+v2+v3, SOCKS5, SSH (v1 and v2), SSHKEY, Subversion, TeamSpeak (TS2), Telnet, VMware-Auth, VNC and XMPP.”

For more information on the options of each protocol in Hydra, you can check the Kali Hydra tool page.

This shows the importance of using a strong password; if your password is common, doesn’t contain special characters and is not above eight characters, it will be prone to be guessed. A one-hundred-million-password list contains common passwords, so when an out-of-the-box application uses an easy password to log in, change it from the default! CCTV cameras and web frameworks often use admin:password as the default login credentials, which is obviously not strong enough.

Installing Hydra

Hydra is already installed on the AttackBox. You can access it by clicking on the Start AttackBox button.

If you prefer to use the in-browser Kali machine, Hydra also comes pre-installed, as is the case with all Kali distributions. You can access it by selecting Use Kali Linux and clicking on Start Kali Linux button.

However, you can check its official repositories if you prefer to use another Linux distribution. For instance, you can install Hydra on an Ubuntu or Fedora system by executing apt install hydra or dnf install hydra. Furthermore, you can download it from its official THC-Hydra repository.

Answer the questions below

Read the above and have Hydra at the ready.

Task 2 Using Hydra

Start the AttackBox by pressing the Start AttackBox button at the top of this page. The AttackBox machine will start in Split-Screen view. If it is not visible, use the blue Show Split View button at the top of the page.

Press the green Start Machine button below to deploy the machine attached to this task, then navigate to http://MACHINE_IP on the AttackBox (this machine can take up to 3 minutes to boot)

Hydra Commands

The options we pass into Hydra depend on which service (protocol) we’re attacking. For example, if we wanted to brute force FTP with the username being user and a password list being passlist.txt, we’d use the following command:

hydra -l user -P passlist.txt ftp://MACHINE_IP

For this deployed machine, here are the commands to use Hydra on SSH and a web form (POST method).

SSH

Option                      Description
-l                    specifies the (SSH) username for login
-P                    indicates a list of passwords
-t                    sets the number of threads to spawn

For example, hydra -l root -P passwords.txt MACHINE_IP -t 4 ssh will run with the following arguments:

Hydra will use root as the username for ssh
It will try the passwords in the passwords.txt file
There will be four threads running in parallel as indicated by -t 4

Post Web Form

We can use Hydra to brute force web forms too. You must know which type of request it is making; GET or POST methods are commonly used. You can use your browser’s network tab (in developer tools) to see the request types or view the source code.

sudo hydra <username> <wordlist> MACHINE_IP http-post-form "<path>:<login_credentials>:<invalid_response>"

Option Description -l the username for (web form) login -P the password list to use http-post-form the type of the form is POST <path> the login page URL, for example, login.php <login_credentials> the username and password used to log in, for example, username=^USER^&password=^PASS^ <invalid_response> part of the response when the login fails -V verbose output for every attempt

Below is a more concrete example Hydra command to brute force a POST login form:

hydra -l <username> -P <wordlist> MACHINE_IP http-post-form "/:username=^USER^&password=^PASS^:F=incorrect" -V

The login page is only /, i.e., the main IP address.
The username is the form field where the username is entered
The specified username(s) will replace ^USER^
The password is the form field where the password is entered
The provided passwords will be replacing ^PASS^
Finally, F=incorrect is a string that appears in the server reply when the login fails

You should now have enough information to put this to practice and brute force your credentials to the deployed machine!

Navigating to http://MACHINE_IP and inspecting the form

Answer the questions below

2.1 Use Hydra to bruteforce molly’s web password. What is flag 1? (Question Hint If you’ve tried more than 30 passwords from RockYou.txt, you are doing something wrong!)


hydra -l molly -P /usr/share/wordlists/rockyou.txt <Target_IP> http-post-form “/login:username=^USER^&password=^PASS^:Your username or password is incorrect.”
hydra -l molly -P /usr/share/wordlists/rockyou.txt 10.10.161.166 http-post-form "/login:username=^USER^&password=^PASS^:Your username or password is incorrect."

Hydra found the valid password for user molly:

Username: molly
Password : sunshine

Use the following credentials To log in

Answer: THM{2673a7dd116de68e85c48ec0b1f2612e}

2.2 Use Hydra to bruteforce molly’s SSH password. What is flag 2?

hydra -l molly -P /usr/share/wordlists/rockyou.txt <Target_IP> -t 4 ssh
hydra -l molly -P /usr/share/wordlists/rockyou.txt 10.10.161.166 -t 4 ssh

· hydra: This is the main command to run Hydra, a tool for brute-force password cracking.

· -l molly: The -l option specifies the username to use during the brute-force attack. Here, “molly” is the username Hydra will attempt to log in with.

· -P /usr/share/wordlists/rockyou.txt: The -P option specifies the password list to use. In this case, /usr/share/wordlists/rockyou.txt is the path to the RockYou wordlist, a common password list used in brute-forcing. Hydra will try each password in this list for the “molly” user.

· <Target_IP>: Replace <Target_IP> with the actual IP address of the target machine you’re trying to access.

· -t 4: The -t option sets the number of parallel tasks (threads). Here, it is set to 4, meaning Hydra will run 4 simultaneous attempts, speeding up the brute-force process.

· ssh: This specifies the protocol or service to attack. In this case, ssh means Hydra will try to log in via the SSH (Secure Shell) service on the target machine.