Chapter 1, Introduction to Penetration Testing and Web Applications, covers the basic concepts of penetration testing, Kali Linux, and web applications. It starts with the definition of penetration testing itself and other key concepts, followed by the considerations to have before engaging in a professional penetration test such as defining scope and rules of engagement. Then we dig into Kali Linux and see how web applications work, focusing on the aspects that are more relevant to a penetration tester.
Chapter 2, Setting Up Your Lab with Kali Linux, is a technical review of the testing environment that will be used through the rest of the chapters. We start by explaining what Kali Linux is and the tools it includes for the purpose of testing security of web applications; next we look at the vulnerable web applications that will be used in future chapters to demonstrate the vulnerabilities and attacks.
Chapter 3, Reconnaissance and Profiling the Web Server, shows the techniques and tools used by penetration testers and attackers to gain information about the technologies used to develop, host and support the target application and identify the first weak spots that may be further exploited, because, following the standard methodology for penetration testing, the first step is to gather as much information as possible about the targets.
Chapter 4, Authentication and Session Management Flaws, as the name suggests, is dedicated to detection, exploitation, and mitigation of vulnerabilities related to the identification of users and segregation of duties within the application, starting with the explanation of different authentication and session management mechanisms, followed by how these mechanisms can have design or implementation flaws and how those flaws can be taken advantage of by a malicious actor or a penetration tester.
Chapter 5, Detecting and Exploiting Injection-Based Flaws, explains detection, exploitation, and mitigation of the most common injection flaws, because one of the top concerns of developers in terms of security is having their applications vulnerable to any kind of injection attack, be it SQL injection, command injection, or any other attack, these can pose a major risk on a web application.
Chapter 6, Finding and Exploiting Cross-Site Scripting (XSS) Vulnerabilities, goes from explaining what is a Cross-Site Scripting vulnerability, to how and why it poses a security risk, to how to identify when a web application is vulnerable, and how an attacker can take advantage of it to grab sensitive information from the user or make them perform actions unknowingly.
Chapter 7, Cross-Site Request Forgery, Identification and Exploitation, explains what is and how a Cross-Site Request Forgery attack works. Then we discuss the key factor to detecting the flaws that enable it, followed by techniques for exploitation, and finish with prevention and mitigation advice.
Chapter 8, Attacking Flaws in Cryptographic Implementations, starts with an introduction on cryptography concepts that are useful from the perspective of penetration testers, such as how SSL/TLS works in general, a review of concepts and algorithms of encryption, and encoding and hashing; then we describe the tools used to identify weak SSL/TLS implementations, together with the exploitation of well-known vulnerabilities. Next, we cover the detection and exploitation of flaws in custom cryptographic algorithms and implementations. We finish the chapter with an advice on how to prevent vulnerabilities when using encrypted communications or when storing sensitive information.
Chapter 9, AJAX, HTML5, and Client Side Attacks, covers the client side of penetration testing web applications, starting from the crawling process of an AJAX application and explaining the developer tools included in modern web browsers. We'll also look at the innovations brought by HTML5 and the new challenges and opportunities it brings to attackers and penetration testers. Next, a section describing the use of developer tools to bypass security controls implemented client-side follows this and the chapter ends with prevention and mitigation advice for AJAX, HTML5 and client-side vulnerabilities.
Chapter 10, Other Common Security Flaws in Web Applications, talks about insecure direct object references, file inclusion, HTTP parameter pollution, and information disclosure vulnerabilities and their exploitation. We end with an advice on how to prevent and remediate these flaws.
Chapter 11, Using Automated Scanners on Web Applications, explains the factors to take into account when using automated scanners and fuzzers on web applications. We also explain how these scanners work and what fuzzing is, followed by usage examples of the scanning and fuzzing tools included in Kali Linux. We conclude with the actions a penetration tester should take after performing an automated scan on a web application in order to deliver valuable results to the application's developer.
