What potential pitfalls should be avoided when programming login functionality in PHP?

One potential pitfall to avoid when programming login functionality in PHP is storing passwords in plain text. It is crucial to securely hash passwords before storing them in the database to prevent unauthorized access in case of a data breach. Additionally, it is important to use prepared statements to prevent SQL injection attacks and validate user input to avoid any potential security vulnerabilities. 

// Hashing the password before storing it in the database
$password = password_hash($_POST['password'], PASSWORD_DEFAULT);

// Using prepared statements to prevent SQL injection
$stmt = $pdo->prepare("SELECT * FROM users WHERE username = ?");
$stmt->execute([$_POST['username']]);
$user = $stmt->fetch();

// Validating user input to avoid security vulnerabilities
if ($user && password_verify($_POST['password'], $user['password'])) {
    // Login successful
} else {
    // Login failed
}

Keywords

SQL injection password hashing session management CSRF protection secure authentication.

Related Questions