An issue was discovered in Joomla! Core before 3.8.8. Inadequate checks allowed users to modify the access levels of user groups with higher permissions.

An issue was discovered in Joomla! Core before 3.8.8. The web install application would autofill password fields after either a form validation error or navigating to a previous install step, and display the plaintext password for the administrator account at the confirmation screen.

An issue was discovered in Joomla! Core before 3.8.8. Inadequate input filtering leads to a multiple XSS vulnerabilities. Additionally, the default filtering settings could potentially allow users of the default Administrator user group to perform a XSS attack.

In Joomla! Core before 3.8.8, inadequate filtering of file and folder names leads to various XSS attack vectors in the media manager.

An issue was discovered in Joomla! Core before 3.8.8. A long running background process, such as remote checks for core or extension updates, could create a race condition where a session that was expected to be destroyed would be recreated.

An issue was discovered in Joomla! Core before 3.8.8. Inadequate checks allowed users to see the names of tags that were either unpublished or published with restricted view permission.

In Joomla! 3.5.0 through 3.8.5, the lack of type casting of a variable in a SQL statement leads to a SQL injection vulnerability in the User Notes list view.

In Joomla! before 3.8.4, the lack of type casting of a variable in a SQL statement leads to a SQL injection vulnerability in the Hathor postinstall message.

In Joomla! before 3.8.4, inadequate input filtering in com_fields leads to an XSS vulnerability in multiple field types, i.e., list, radio, and checkbox

In Joomla! before 3.8.4, inadequate input filtering in the Uri class (formerly JUri) leads to an XSS vulnerability.