An issue was discovered in Joomla! before 3.9.3. Inadequate parameter handling in JavaScript code (core.js writeDynaList) could lead to an XSS attack vector.
An issue was discovered in Joomla! before 3.9.3. A combination of specific web server configurations, in connection with specific file types and browser-side MIME-type sniffing, causes an XSS attack vector.
An issue was discovered in Joomla! before 3.9.3. The phar:// stream wrapper can be used for objection injection attacks because there is no protection mechanism (such as the TYPO3 PHAR stream wrapper) to prevent use of the phar:// handler for non .phar-files.