Zploit 0-Day Shell

:: Editing File: payment_backup.php

<?php
session_start();
include "db.php";

if (!isset($_GET['user_id'])) {
    die("Invalid Access");
}

$user_id = intval($_GET['user_id']);

// fetch user
$user = mysqli_fetch_assoc(mysqli_query($conn, "SELECT * FROM users WHERE id=$user_id"));
if (!$user) { die("Invalid User"); }

// Payment details
$amount = 1;
$upi_id = "9768676862@ptsbi";
$merchant_name = "Kreativepixelz";

// UPI Link
$upi_link = "upi://pay?pa={$upi_id}&pn={$merchant_name}&tn=AppPayment&am={$amount}&cu=INR";

// Insert payment row if not exists
$chk = mysqli_query($conn, "SELECT * FROM payments WHERE user_id=$user_id");
if (mysqli_num_rows($chk) == 0) {
    mysqli_query($conn, "INSERT INTO payments (user_id, amount, upi_id, status) 
                         VALUES ($user_id, $amount, '$upi_id', 'pending')");
}

<!DOCTYPE html>
<html>
<head>
<title>Payment Step</title>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css">
</head>

<h3 class="text-center mb-3">Complete Your Payment</h3>

<p class="text-center">Amount: <b>₹<?php echo $amount; ?></b></p>
<hr>

<h5>Option 1: Google Pay / PhonePe / UPI App</h5>

<a href="<?php echo $upi_link; ?>" class="btn btn-success w-100 mb-3">
    Pay with Google Pay / UPI
</a>

<h5 class="mt-3">Option 2: Scan QR Code</h5>

<hr>

<form action="verify_payment.php" method="POST">

<label>Enter UPI Transaction ID / UTR No*</label>
    <input type="text" class="form-control" name="transaction_id" required>

<button class="btn btn-primary w-100 mt-3">Submit Payment</button>

</form>

</div>
</div>
</div>

</body>
</html>