DOM-Based XSS Vulnerability

Anandhu Krishnan
Published on
13 May 2024


Cross-Site Scripting (DOM-Based) occurs when malicious scripts are executed in a user’s browser as a result of manipulating the Document Object Model (DOM) directly. Unlike traditional XSS, which relies on server-side code to inject scripts, DOM-based XSS attacks occur entirely on the client side. Attackers exploit vulnerabilities in client-side scripts to alter the DOM, executing unintended code within the user’s browser. This can lead to data theft, session hijacking, and manipulation of web page content, undermining user trust and security.


  • Avoid client-side sensitive actions like rewriting or redirection using client-side data.
  • Apply a proper authentication on the client side code.
  • Implement an intrusion prevention systems in the server.
  • Avoid including untrusted data in this context.
  • Escape the JavaScript code before inserting untrusted data into the HTML Attribute Subcontext.
  • Implement URL escape before Inserting Untrusted Data into URL Attribute Subcontext.
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Written by
Anandhu Krishnan
Anandhu Krishnan
Lead Engineer
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