Hack the Login

Hack the Login

Start the machine, hack the system, and find the hidden flags to complete this challenge and earn points!

On this challenge from @hackerdna we must find a way to login on the system, the challenge can be found here https://hackerdna.com/labs/hack-the-login

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Once we startup the lab and connect we notice there is login screen

So, the very first thing I always do is check the source code, so if we inspect it we will see a js is called, script.js

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Authentication</title>
    <link rel="stylesheet" href="style.css">
</head>
<body>
    <div class="container">
        <div class="login-box">
            <h2>Login</h2>
            <form id="loginForm">
                <div class="input-group">
                    <label for="username">Username:</label>
                    <input type="text" id="username" name="username" required>
                </div>
                <div class="input-group">
                    <label for="password">Password:</label>
                    <input type="password" id="password" name="password" required>
                </div>
                <button type="submit">Login</button>
            </form>
            <div id="message"></div>
        </div>
    </div>
    <script src="script.js"></script>
</body>
</html>

If we click on it

document.getElementById('loginForm').addEventListener('submit', function(e) {
    e.preventDefault();

    const username = document.getElementById('username').value;
    const password = document.getElementById('password').value;
    const messageDiv = document.getElementById('message');

    // Simple authentication check
    if (username === "admin" && password === "SecretPassword123!") {
        messageDiv.textContent = "Authentication successful! Retrieving flag...";
        messageDiv.className = "success";

        // Read the flag from the random folder
        fetch('7d9f3b2e1c8a5f6d4e0/flag.txt')
            .then(response => response.text())
            .then(flag => {
                messageDiv.textContent = `Success! Flag: ${flag}`;
            })
            .catch(error => {
                messageDiv.textContent = "Error reading flag file";
                messageDiv.className = "";
            });
    } else {
        messageDiv.textContent = "Invalid username or password";
        messageDiv.className = "";
    }
});

We can see several things:

• The username: admin
• The password: SecretPassword123!
• The path to the flag: 7d9f3b2e1c8a5f6d4e0/flag.txt

So, to grab the flag we can simple type username and password or simplier, just add the path to the url to get the flag