The web application uses SAML. The web application's SAML Consumer Service XML parser is vulnerable to XXE.
XML supports a facility known as "external entities"(XXE), which instructs an XML processor to retrieve and perform an inline include of XML located at a particular URI. An external XML entity can be used to append or modify an XML document.
An unauthenticated attacker may be able to use it in order to read arbitrary files on the server or send requests to other servers (SSRF).
Disable parsing of XML external entities.