Google Chrome before 42.0.2311.90 does not always ask the user before proceeding with CONTENT_SETTINGS_TYPE_FULLSCREEN and CONTENT_SETTINGS_TYPE_MOUSELOCK changes, which allows user-assisted remote attackers to cause a denial of service (UI disruption) by constructing a crafted HTML document containing JavaScript code with requestFullScreen and requestPointerLock calls, and arranging for the user to access this document with a file: URL.