dotCMS before 22.06 allows remote attackers to bypass intended access control and obtain sensitive information by using a semicolon in a URL to introduce a matrix parameter. (This is also fixed in 5.3.8.12, 21.06.9, and 22.03.2 for LTS users.) Some Java application frameworks, including those used by Spring or Tomcat, allow the use of matrix parameters: these are URI parameters separated by semicolons. Through precise semicolon placement in a URI, it is possible to exploit this feature to avoid dotCMS's path-based XSS prevention (such as "require login" filters), and consequently access restricted resources. For example, an attacker could place a semicolon immediately before a / character that separates elements of a filesystem path. This could reveal file content that is ordinarily only visible to signed-in users. This issue can be chained with other exploit code to achieve XSS attacks against dotCMS.