Road to CEH Masters Week 13: Hacking Web Servers

Understanding and Preventing Web Server Attacks

Introduction to Web Servers

Web servers are critical components in the internet infrastructure, storing, processing, and delivering web pages to clients via HTTP. They consist of several components, including the document root, server root, virtual document tree, virtual hosting, and web proxy. Popular architectures include the LAMP stack (Linux, Apache, MySQL, PHP) and Microsoft IIS (Internet Information Services).

Common Web Server Security Issues

1. Vulnerabilities and Attacks:
   • Attackers exploit software vulnerabilities and configuration errors to compromise web servers.
   • Goals range from financial gains (e.g., stealing credit card information) to technical exploits (e.g., compromising databases or integrating servers into botnets).
2. Dangerous Security Flaws:
   • Common security flaws include lack of updates, credential reuse, unrestricted traffic, and unhardened applications.
   • Impacts of attacks include data theft, website defacement, secondary attacks, root access, data tampering, and reputation damage.

Why Web Servers Are Compromised

• Webmaster’s Perspective: Bugs in software programs and the open architecture of web servers pose inherent risks.
• Network Administrator’s Perspective: Poorly configured web servers can create potential security holes in the LAN.
• End User’s Perspective: Active content like ActiveX controls and Java applets can serve as conduits for malicious software.

Common Web Server Attacks

1. DNS Server Hijacking: Attackers redirect user requests to rogue servers by compromising DNS settings.
2. DNS Amplification Attack: Attackers use recursive DNS queries to launch DDoS attacks.
3. Directory Traversal Attacks: Attackers access restricted directories by exploiting vulnerabilities in web server software.
4. Website Defacement: Unauthorized changes to website content, often using methods like SQL injection.
5. Web Server Misconfiguration: Configuration weaknesses that can be exploited for various attacks.
6. HTTP Response-Splitting Attack: Manipulating HTTP headers to split responses and inject malicious content.
7. Web Cache Poisoning Attack: Swapping cached content with infected content to serve malicious content to users.
8. SSH Brute Force Attacks: Obtaining login credentials through brute-force attacks on SSH protocols.
9. Web Server Password Cracking: Exploiting weak passwords using methods like dictionary attacks, brute-force attacks, and hybrid attacks.
10. DoS/DDoS Attack: Overwhelming web servers with fake requests to make them unavailable to legitimate users.
11. Man-in-the-Middle Attack: Intercepting and altering communications between end users and web servers to steal sensitive information.

Preventive Measures

• Regularly update and patch web server software.
• Implement strong authentication mechanisms.
• Harden applications and restrict traffic.
• Configure web servers properly to avoid vulnerabilities.
• Monitor and secure all aspects of the web server environment.

By understanding these concepts and taking proactive measures, organizations can significantly reduce the risk of web server attacks and ensure the security of their web infrastructure.

With my study notes I have create a set of 11 flashcards that can be accessed here: Module 13 – Flash Cards

I have also created this visual Mind map: Module 13 – Mindmap

If you have any questions or any feedback feel free to comment or leave a message on the homepage as that will send directly to me!

Thanks for reading!