Exploit for Improper Input Validation in Google Chrome

## https://sploitus.com/exploit?id=8AC20347-7D7F-5EFD-90EB-D4E263FCED51
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## CVE-2026-11113 – SMTP Header Injection in Contact Form

### Program Code (Python)

```python
# contact_form_server.py - Mails feedback without sanitizing headers
from flask import Flask, request
import smtplib

app = Flask(__name__)

@app.route('/contact', methods=['POST'])
def contact():
    sender = request.form['email']
    message = request.form['message']
    # Vulnerable: constructs raw headers with user input
    headers = f"From: {sender}\r\nTo: admin@example.com\r\nSubject: Feedback"
    msg = f"{headers}\r\n\r\n{message}"
    # Insecurely sending via SMTP (simulated print)
    print("Would send:\n", msg)
    return "Message sent"

if __name__ == '__main__':
    app.run(port=5000)

```

# CVE-2026-11113 – SMTP Header Injection in Contact Form

![Severity: High](https://img.shields.io/badge/severity-high-orange)

## Overview
A contact form directly inserts user‑supplied email address into the mail header without sanitization. An attacker can inject newline characters to add arbitrary SMTP headers, such as `Bcc`, enabling spam relay and phishing.

## Vulnerability Details
- **Type:** SMTP Header Injection
- **Impact:** Spam distribution, email spoofing.
- **Root Cause:** User input is used to build raw email headers without removing carriage‑return and line‑feed characters.

## Exploit Demonstration
1. Start the form server:
   ```bash
   pip install flask
   python contact_form_server.py
2. Run the exploit:
   ```bash
   python exploit_smtp_header_injection.py

The server prints a message with the injected Bcc lines, demonstrating how additional recipients would receive the email.