An issue was discovered in Total.js CMS 12.0.0. An authenticated user with the Pages privilege can conduct a path traversal attack (../) to include .html files that are outside the permitted directory. Also, if a page contains a template directive, then the directive will be server side processed. Thus, if a user can control the content of a .html file, then they can inject a payload with a malicious template directive to gain Remote Command Execution. The exploit will work only with the .html extension.