Easy and Common Vulnerabilities: A Beginner’s Guide to Bug Hunting

Cybersecurity is a dynamic field with increasing demand for skilled professionals who can identify and mitigate vulnerabilities in digital systems. Bug hunting, also known as ethical hacking, is an exciting and essential aspect of cybersecurity. Beginners in the field often wonder where to start and what vulnerabilities they should focus on. In this blog, we will explore some of the easy and common vulnerabilities that beginners can target and how to find them.

1. Cross-Site Scripting (XSS)

Cross-Site Scripting, or XSS, is a prevalent web application vulnerability. It occurs when an attacker injects malicious scripts into a web application, which are then executed by unsuspecting users.

How to Find XSS Vulnerabilities:

• Begin by exploring the target website and looking for input fields, such as search bars, contact forms, or comment sections.
• Inject simple scripts like <script>alert('XSS')</script> into these fields to see if the website reflects the input back to you.
• Observe if the script you injected runs, which indicates a potential XSS vulnerability.

2. SQL Injection

SQL Injection is another common web application vulnerability where an attacker manipulates the input fields to execute malicious SQL queries on a database.

How to Find SQL Injection Vulnerabilities:

• Look for input fields where data is sent to a database, such as search boxes or login forms.
• Attempt to insert SQL statements into these fields, like ‘ OR ‘1’=’1, and check if the application responds with unintended data.
• If the application displays database-related errors or responds strangely, it might be vulnerable to SQL injection.

3. Cross-Site Request Forgery (CSRF)

Cross-Site Request Forgery is an attack that tricks a user into performing actions they did not intend to on a different site. It often occurs with functions like changing a password or making transactions.

How to Find CSRF Vulnerabilities:

• Identify actions that can be performed without user authentication, such as updating email addresses or profile images.
• Create a web page with malicious code that triggers these actions.
• Send the victim a link to your page and see if they perform the action without intending to.

4. Insecure Direct Object References (IDOR)

Insecure Direct Object References occur when an attacker can access, modify, or delete objects such as files, database records, or URLs without proper authorization.

How to Find IDOR Vulnerabilities:

• Examine the application’s URL structure and any parameters that appear in the URL.
• Modify those parameters to access resources that should not be accessible.
• If you can access or manipulate unauthorized objects, you may have found an IDOR vulnerability.

5. Unvalidated Redirects and Forwards

This vulnerability occurs when an application redirects or forwards users to external websites without validating the target URL, which can lead to phishing attacks or other malicious actions.

How to Find Unvalidated Redirects and Forwards:

• Look for links or buttons that redirect users to external websites.
• Modify the URL to point to a different site.
• If the application allows this without validation, it may have a vulnerability.

Conclusion

Bug hunting is a valuable and rewarding skill in the field of cybersecurity. As a beginner, targeting easy and common vulnerabilities like XSS, SQL injection, CSRF, IDOR, and unvalidated redirects and forwards is a great starting point. Remember that ethical hacking is about finding and responsibly reporting vulnerabilities, not exploiting them. Always ensure you have proper authorization and permission to test systems, and follow responsible disclosure practices when reporting vulnerabilities to organizations. Happy bug hunting!