Book Image

Becoming the Hacker

By : Adrian Pruteanu
Book Image

Becoming the Hacker

By: Adrian Pruteanu

Overview of this book

Becoming the Hacker will teach you how to approach web penetration testing with an attacker's mindset. While testing web applications for performance is common, the ever-changing threat landscape makes security testing much more difficult for the defender. There are many web application tools that claim to provide a complete survey and defense against potential threats, but they must be analyzed in line with the security needs of each web application or service. We must understand how an attacker approaches a web application and the implications of breaching its defenses. Through the first part of the book, Adrian Pruteanu walks you through commonly encountered vulnerabilities and how to take advantage of them to achieve your goal. The latter part of the book shifts gears and puts the newly learned techniques into practice, going over scenarios where the target may be a popular content management system or a containerized application and its network. Becoming the Hacker is a clear guide to web application security from an attacker's point of view, from which both sides can benefit.
Table of Contents (18 chapters)
Becoming the Hacker
Contributors
Preface
Index

RFI


Although not as common in modern applications, RFI vulnerabilities do still pop up from time to time. RFI was popular back in the early days of the web and PHP. PHP was notorious for allowing developers to implement features that were inherently dangerous. The include() and require() functions essentially allowed code to be included from other files, either on the same disk or over the wire. This makes web applications more powerful and dynamic but comes at a great cost. As you can imagine, allowing user data to pass to include() unsanitized can result in application or server compromise.

The danger of allowing remote files to be included in server-side code is pretty obvious. PHP will download the remote text and interpret it as code. If the remote URL is controlled by the attacker, they could easily feed the application a shell.

In the following example, the RFI vulnerability can be exploited using a simple system() passthrough shell. On the attacker-controlled c2.spider.ml server, a...