The "xml.etree.ElementTree" module that mofh used up until version "1.0.1" implements a simple and efficient API for parsing and creating XML data. But it makes the application vulnerable to: - "Billion Laughs attack" (https://en.wikipedia.org/wiki/Billion_laughs_attack): It is a type of denial-of-service attack aimed at XML parsers. It uses multiple levels of nested entities. If one large entity is repeated with a couple of thousand chars repeatedly, the parser gets overwhelmed. - "Quadratic blowup attack" (https://www.acunetix.com/vulnerabilities/web/xml-quadratic-blowup-denial-of-service-attack/): It is similar to a Billion Laughs attack. It abuses entity expansion, too. Instead of nested entities, it repeats one large entity with a couple of thousand chars repeatedly. The Problem has been patched starting from version "1.0.1" by utilising the "defusedxml" package instead of "xml.etree.ElementTree".