Day 13 of 30 Days — 30 Vulnerabilities | XML External Entity (XXE)

Day 13: Mastering XML External Entity (XXE) Vulnerability — Essential Tricks & Techniques Based on Personal Experience and Valuable POCs

[ In collaboration with Abhijeet Kumawat ( his LinkedIn | Twitter)]

Hey geeks, it4chis3c (Twitter) here with one more write-up on tricks & tips to detect XML External Entity (XXE) Vulnerability.

1. Brief Description

• Definition: XXE is an attack that exploits XML parsers that improperly process external entities.
• Impact: Allows attackers to read local files, execute remote requests, and in some cases, execute code or cause Denial of Service (DoS).
• Common Targets: Systems accepting XML input, including web services, SOAP APIs, and XML-based file uploads.

2. Where to Detect

• User Inputs: Forms or fields accepting XML input.
• File Uploads: Systems allowing XML file uploads.
• APIs: SOAP or REST APIs using XML.
• Document Processing: Applications that process XML documents, including Office files and SVGs.
• Configuration Files: Any place where XML configuration files are processed.