# XXE (XML External Entities)

* XXE is a web vulnerability that allows an attackermto interfere with an application's processing of XML data. 
* It often allows reading of files present over application server filesystem, and  interaction with any back-end or external systems that application itself can access (SSRF).<br>

[Why Entity Stacking/ Nesting Required in blind xxe ?](https://www.reddit.com/r/cybersecurity/comments/17s7hi9/importance_of_stacking_entities_in_a_xxe/?rdt=63263)

What is need for hosting the malicious DTD file?\
It required becaurse, the application allows only addition of one Entity inside XML, if we try to add more than one it gives Error ("Entities are not allowed for security reasons").


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