Ethical Hacking Tutorial: Bypassing Login Credentials with Burp Suite

Table of Contents

• Introduction to Ethical Hacking Techniques
• Step-by-Step Tutorial on Cracking Passwords
• Bypassing Login Screens with Burp Suite
• Ethical Considerations for Penetration Testing
• Conclusion and Key Takeaways

Introduction to Ethical Hacking Techniques for Penetration Testing

Ethical hacking, also known as penetration testing or pen testing, involves using the same tools and techniques as malicious hackers, but with permission from an organization to assess the security of their systems. As cyberattacks become more sophisticated, pen testing has become an essential practice for identifying vulnerabilities before they can be exploited. In this blog post, we will explore some common ethical hacking techniques using tools like Burp Suite to intercept traffic and brute force password cracking.

It's important to note that all of the techniques discussed should only be used with explicit permission from owners of the systems tested. Ethical hacking must follow responsible disclosure policies and industry best practices to ensure testing is conducted legally and ethically.

Overview of Common Hacking Methods like SQL Injection and XSS

Many of the techniques used by ethical hackers are similar to those used by malicious actors. Some common methods include: SQL injection involves inserting malicious SQL code into application input fields to access or modify backend databases. Hackers can use SQL injection to extract sensitive data like passwords or credit cards. Cross-site scripting (XSS) enables attackers to inject client-side scripts into web pages viewed by other users. This could allow bypassing access controls or stealing session cookies. Brute force attacks try guessing all possible passwords or passphrases to gain unauthorized access to systems. Social engineering manipulates users into handing over confidential information or performing actions like downloading malware. Distributed denial-of-service (DDoS) floods systems with traffic to make them unavailable to legitimate users.

Using Burp Suite for Intercepting Traffic and Launching Attacks

Burp Suite is a popular tool used by ethical hackers for a number of purposes: The built-in proxy allows intercepting traffic between a browser and server. This enables examining requests and responses to find vulnerabilities. The intruder tool automates customized attacks like brute force password guessing and SQL injection. Repeater makes it easy to manually modify and resend individual requests to test different payloads. Burp Suite Community Edition provides many of the core features needed for pen testing and is available for free.

Step-by-Step Tutorial on Cracking Passwords with a Brute Force Attack

One common task for security testers is determining if account passwords can be discovered through brute force attacks. Here is an overview of the process:

First, the tester captures a set of failed login attempts to identify the error message format and fields like usernames. This is often done using a proxy like Burp Suite to intercept the traffic.

Next, the Burp Intruder tool is configured to perform a brute force password guessing attack. The wordlist of passwords is loaded as payloads. The login error message is set as a match string to identify successful guesses.

Finally, the attack is launched through Burp Suite which tries all the different passwords. By analyzing the responses, testers can determine which password triggers a different response indicating a successful login.

Capturing Login Attempts for Analysis

Proxying traffic through Burp Suite allows capturing failed login attempts to the target application. The intercepted requests can be examined to identify the structure of login submissions and error response messages. Parameters like usernames and passwords can be marked in Burp for targeting with the attack. The response content can also be searched to find a unique string in failed logins to use for identifying successes later.

Configuring and Launching a Brute Force Attack in Burp

Once the analysis is done, Burp Intruder can be leveraged to perform customized brute force password guessing. The marked login parameters are set as attack points. A wordlist of passwords is loaded as payloads. 'Attack type' is set to 'Sniper' to iterate through password guesses. The match string from a failed login is entered under 'Grep - Match'. Any responses that differ from this indicate a credential guess could be correct. With the attack configured, the 'Start attack' button launches the brute forcing. Hackers will analyze the results to find guesses that triggered different responses to reveal working credentials.

Examining Attack Results to Determine Cracked Passwords

After the brute force attack completes, the results need analysis to determine if any passwords were discovered. The responses are scanned looking for any that differ from the defined error string. The matches indicate the payload password may be correct. These potential working credentials can then be verified manually by logging into the application with that username and password combination. Any successfully determined passwords demonstrate the system's vulnerability to online brute force attacks.

Bypassing Login Screens with Burp Suite Session Handling Tricks

Instead of brute forcing passwords, testers can also try to bypass login pages altogether by manipulating session handling.

Once an active session is established, cookies with identifying session IDs are stored in the browser. Burp can be used to intercept these cookies.

The cookies can then be sent to Burp Repeater. By removing the login page reference, and adding cookies to the request headers, access may be gained.

If successful, this technique allows accessing authenticated pages without valid credentials, revealing vulnerabilities in session management.

Ethical Considerations for Responsible Penetration Testing

While using hacking techniques for authorized testing, it is critical to maintain proper ethics and responsibility:

Responsible disclosure policies give companies reasonable timelines to patch vulnerabilities before details become public.

Following industry standards and best practices ensures tests are conducted safely and legally.

Proper scope and rules of engagement should be agreed to detailing what systems can and cannot be accessed.

Tester access to systems and data should be limited and monitored to what is necessary for the engagement.

Obtained credentials and sensitive data should be securely retained and destroyed after testing completes.

Implementing Responsible Disclosure Policies

Responsible disclosure involves reporting vulnerabilities privately to owners first before releasing details publicly. This gives companies a reasonable timeframe to fix issues before exploits may be developed. Standard disclosure terms often allow 30-90 days before going public with vulnerabilities. Public disclosure ensures transparency and allows others to validate the findings.

Following Best Practices for Legal and Ethical Pen Tests

Standards like the Penetration Testing Execution Standard provide methodologies for safe and controlled testing. Best practices include getting written permission, defining scope and rules of engagement, regulatory compliance, proper reporting and more. Following such standards minimizes risks and ensures tests are conducted legally and ethically.

Conclusion and Key Takeaways on Ethical Hacking

To summarize, ethical hacking employs the same tools and techniques used by malicious actors, but in a legal and authorized way to assess system security.

Methods like SQL injection, XSS, brute forcing, DDoS, and social engineering are tested to identify vulnerabilities.

Burp Suite is a popular tool for traffic interception, manual manipulation, and automating customized attacks.

Cracking passwords through brute forcing is one common penetration testing task that can reveal account vulnerabilities.

Bypassing authentication can also be tested by reusing stolen session cookies with Burp Repeater.

However, it's critical that penetration tests follow responsible disclosure and industry best practices for legal, ethical engagements.

FAQ

Q: Is password cracking illegal?
A: Ethical, authorized penetration testing for security improvements is legal. Randomly cracking passwords without permission is illegal.

Q: What is the best password cracking tool?
A: Burp Suite is an industry-standard web app penetration testing tool useful for many ethical hacking techniques.

Q: How can I learn ethical hacking?
A: Start by learning cybersecurity fundamentals before advancing to specialized tools. Always get authorization and have a responsible disclosure policy.