Resolving Security Issues Unearthed During a Pen Test
Tags: pentest, cybersecurity
Published: 2023-09-12 09:16:34

Penetration testing, often referred to as pen testing, is a crucial component of any robust cybersecurity strategy. It allows organizations to uncover vulnerabilities and weaknesses in their applications and systems before malicious actors can exploit them. However, the real value of a pen test lies not just in finding security issues but also in addressing and resolving them promptly. In this blog, we'll explore how to effectively resolve security issues discovered during a pen test, using real-world examples like XSS (Cross-Site Scripting), SQL injection, session timeout etc.
Here we will take a .NET app as a reference.

**Cross-Site Scripting (XSS)**
Cross-Site Scripting is a prevalent vulnerability that occurs when a web application allows users to inject malicious scripts into web pages viewed by other users. To resolve XSS issues:
a. Input Validation: Ensure that all user inputs are validated and sanitized before rendering them in HTML or JavaScript.
b. Output Encoding: Implement output encoding to prevent script execution.
c. Security Headers: Employ security headers like Content Security Policy (CSP) to restrict the sources of executable scripts.
d. Regular Updates: Regularly update and patch your web application framework and libraries to mitigate known XSS vulnerabilities.

**SQL Injection**
SQL injection is another critical security concern that arises when an attacker manipulates an application's SQL query to access unauthorized data. To address SQL injection issues:
a. Parameterized Queries: Use parameterized queries or prepared statements to separate user input from SQL queries, making it nearly impossible for attackers to inject malicious SQL.
b. Input Validation: Validate and sanitize user input to detect and block any attempts at injecting malicious SQL code.
c. Escaping Characters: Implement proper escaping of special characters in SQL queries to prevent injection.
d. Principle of Least Privilege: Ensure that database connections have the least privilege required for the application, limiting potential damage if an injection occurs.

**Session Timeout**
Session timeout issues can lead to unauthorized access when users leave their sessions unattended. To resolve session timeout problems:
a. Set Reasonable Timeouts: Define appropriate session timeout periods based on the sensitivity of the application. Shorter timeouts for more critical applications, longer for less critical ones.
b. User Notifications: Notify users before their sessions expire and provide an option to extend the session if needed.
c. Implement Idle Timeout: Implement idle session timeouts to automatically log out users after a period of inactivity.
d. Persistent Sessions: Use persistent sessions for users who need to remain logged in for longer periods, but always ensure secure handling of these sessions.

**Upgrading Libraries in a .NET Application**
Regularly upgrading libraries and dependencies is crucial to maintaining a secure application. Here's how to tackle this issue in a .NET application:
a. Dependency Scanning: Utilize tools and services that can scan your application for outdated or vulnerable dependencies, such as OWASP Dependency-Check.
b. Version Control: Maintain a version control system to track changes in your application's dependencies.
c. Automated Testing: Integrate automated testing into your development pipeline to identify compatibility issues and vulnerabilities when updating libraries.
d. Patch Management: Develop a patch management process to ensure timely updates and patches are applied when security vulnerabilities are discovered.

Resolving the issues uncovered during a pen test requires a systematic approach that includes input validation, output encoding, parameterized queries, session management, and diligent library management. By addressing these issues promptly and effectively, you can significantly enhance the security posture of your organization and reduce the risk of data breaches and cyberattacks.