Web Application Penetration Testing

The discovery phase is a crucial part of a web application penetration test, focusing on identifying vulnerabilities and weaknesses within the application’s architecture and functionalities. This phase builds on the information gathered during the reconnaissance and mapping phases to uncover potential security issues that could be exploited by attackers. Here’s an overview of the discovery phase:

1. Vulnerability Scanning

• Automated Scanners: Use automated vulnerability scanning tools like OWASP ZAP, Burp Suite, or Nessus to scan the web application for common vulnerabilities. These tools help identify issues such as SQL injection, cross-site scripting (XSS), insecure configurations, and outdated software.
• Manual Verification: Complement automated scanning with manual verification of identified vulnerabilities. This step ensures that false positives are filtered out and true vulnerabilities are accurately assessed.

2. Testing for Injection Flaws

• SQL Injection: Test input fields, URLs, and API endpoints for SQL injection vulnerabilities by attempting to inject SQL commands. Check for improper input validation and error-based or blind SQL injection issues.
• Command Injection: Identify areas where the application executes system commands based on user input and test for command injection vulnerabilities by injecting malicious commands.

3. Cross-Site Scripting (XSS)

• Stored XSS: Test input fields and data storage mechanisms to identify stored XSS vulnerabilities, where malicious scripts are saved on the server and executed in other users’ browsers.
• Reflected XSS: Test for reflected XSS by injecting scripts into URLs and form submissions, which are immediately reflected back to the user in the response.

4. Cross-Site Request Forgery (CSRF)

• CSRF Tokens: Check for the presence and proper implementation of CSRF tokens in forms and state-changing requests. Ensure that tokens are unique for each session and request.
• CSRF Attacks: Simulate CSRF attacks by crafting malicious requests to see if the application performs unintended actions without proper validation.

5. Authentication and Session Management

• Brute Force Attacks: Test authentication mechanisms for susceptibility to brute force attacks by attempting to guess passwords or bypass authentication.
• Session Hijacking: Analyze session management to identify weaknesses that could allow session hijacking. This includes testing for insecure session IDs, lack of session expiration, and improper handling of session tokens.

6. File Upload Vulnerabilities

• File Type Validation: Test file upload functionalities to ensure proper validation and restriction of file types. Check for the ability to upload executable files or scripts.
• Path Traversal: Test for path traversal vulnerabilities by attempting to upload files to unintended directories or access restricted files on the server.

7. Insecure Direct Object References (IDOR)

• Access Control: Test for IDOR vulnerabilities by manipulating parameters in URLs or API requests to access or modify data belonging to other users without proper authorization checks.

8. Security Misconfigurations

• Server and Application Configurations: Identify and test for misconfigurations in the web server, application server, and application settings that could expose sensitive information or allow unauthorized access.
• Default Credentials: Check for the use of default credentials in administrative interfaces and other sensitive areas.

9. Third-Party Component Analysis

• Dependency Scanning: Analyze the web application’s use of third-party libraries and frameworks to identify known vulnerabilities. Use tools like Snyk or Retire.js to scan for vulnerable dependencies.
• Patch Management: Check if the application and its components are up-to-date with the latest security patches and updates.

The exploitation phase of a web application penetration test is where the identified vulnerabilities are actively exploited to understand the real-world impact they can have on the application and its users. This phase is critical for demonstrating the risks associated with the vulnerabilities and for providing concrete evidence to support remediation efforts. Here’s an overview of the exploitation phase:

1. Exploiting Identified Vulnerabilities

• SQL Injection: Use crafted SQL queries to exploit SQL injection vulnerabilities, gaining unauthorized access to the database, extracting sensitive data, or manipulating the database content.
• Cross-Site Scripting (XSS): Inject malicious scripts into the application to exploit XSS vulnerabilities, demonstrating how attackers can steal cookies, session tokens, or perform actions on behalf of users.
• Command Injection: Execute system commands through vulnerable input fields to demonstrate how an attacker can gain control over the underlying server or execute arbitrary commands.

2. Privilege Escalation

• Horizontal Privilege Escalation: Exploit vulnerabilities to access data or perform actions meant for other users with the same privilege level.
• Vertical Privilege Escalation: Exploit vulnerabilities to escalate privileges and gain access to administrative functionalities or sensitive data restricted to higher privilege users.

3. Session Hijacking

• Session Token Manipulation: Exploit vulnerabilities in session management to hijack user sessions. This includes capturing session tokens through XSS or sniffing and then using them to impersonate users.
• Session Fixation: Set session tokens for users and exploit the application’s session handling to take over the sessions once the users authenticate.

4. Cross-Site Request Forgery (CSRF)

• Crafting Malicious Requests: Create malicious links or forms to exploit CSRF vulnerabilities, forcing authenticated users to perform unwanted actions such as changing account settings or initiating transactions.

5. Insecure Direct Object References (IDOR)

• Parameter Manipulation: Modify parameters in requests to access or manipulate data belonging to other users, demonstrating unauthorized access to sensitive information.

6. File Upload Exploits

• Uploading Malicious Files: Upload scripts or executables to exploit vulnerabilities in file upload functionalities. This could lead to remote code execution or complete system compromise.
• Path Traversal: Exploit path traversal vulnerabilities to upload files to unintended locations or overwrite critical files on the server.

7. Bypassing Authentication and Authorization

• Brute Force Attacks: Conduct brute force attacks to guess passwords or bypass authentication mechanisms.
• Authorization Bypass: Exploit flaws in authorization logic to gain access to restricted functionalities or data.

The reporting phase of a web application penetration test is the culmination of all the testing efforts, where findings are documented in a clear, concise, and actionable manner. This phase is crucial for communicating the results of the pen test to stakeholders, providing them with the information needed to understand the vulnerabilities identified and the steps necessary to mitigate them. Here’s an overview of the reporting phase:

1. Executive Summary

• Overview of Findings: Provide a high-level summary of the key findings from the penetration test. This section should highlight the most critical vulnerabilities, the overall security posture of the application, and the potential business impact.
• Risk Assessment: Summarize the risk levels associated with the identified vulnerabilities, using a standardized scoring system such as CVSS (Common Vulnerability Scoring System) or DREAD (Damage, Reproducibility, Exploitability, Affected Users, Discoverability).

2. Detailed Findings

• Vulnerability Description: For each identified vulnerability, provide a detailed description, including how it was discovered, the technical details, and the specific component or functionality affected.
• Evidence of Exploitation: Include evidence such as screenshots, logs, or output from exploited vulnerabilities to demonstrate the impact and confirm the findings.
• Risk Rating: Assign a risk rating to each vulnerability, considering factors such as exploitability, potential damage, and the number of affected users. This helps prioritize remediation efforts.

3. Technical Details

• Proof of Concept (PoC): Where applicable, include proof of concept code or detailed steps that were used to exploit the vulnerability. This helps developers understand the exact nature of the issue and how it can be reproduced.
• Attack Scenarios: Describe potential attack scenarios that could be executed by exploiting the identified vulnerabilities. This provides context on how an attacker could leverage the vulnerabilities to achieve their goals.

4. Impact Analysis

• Business Impact: Discuss the potential business impact of the identified vulnerabilities, including data breaches, financial loss, reputational damage, and compliance issues.
• User Impact: Describe how the vulnerabilities could affect end-users, such as exposing personal information, enabling account takeovers, or disrupting services.

5. Recommendations

• Remediation Steps: Provide detailed remediation steps for each vulnerability, including code changes, configuration adjustments, and updates to security policies. This section should offer clear and actionable guidance to fix the issues.
• Best Practices: Suggest best practices for improving overall security, such as secure coding practices, regular security training for developers, and implementing security controls like input validation and proper authentication mechanisms.

6. Conclusion

• Summary of Overall Security Posture: Offer a final assessment of the web application’s security posture based on the findings from the penetration test. Highlight areas of strength and weakness.
• Next Steps: Recommend follow-up actions, such as re-testing after remediation and periodic penetration testing to ensure ongoing security.