XXE Injection

Introduction

XXE (XML External Entity) injection is a type of security flaw that exploits vulnerabilities in an application's XML input. It occurs when an application accepts XML input that includes external entity references within the XML itself. Attackers can leverage this vulnerability to disclose local files, make server-side requests, or execute remote code.

Given the widespread use of XML in web applications, particularly in web services and SOAP-based APIs, the severity of these vulnerabilities cannot be underestimated.

Objectives

1. Recognize the fundamental concepts and dangers associated with XXE injection.
2. Identify vulnerable XML processing configurations and practices.
3. Develop techniques for detecting, exploiting, and mitigating XXE vulnerabilities in applications.

Prerequisites

1. Knowledge of how XML documents are structured, including tags, attributes, and entity references.
2. Familiarity with how web applications process input and manage data.
3. Basic knowledge of OWASP ZAP or Burp Suite.