Php Email Form Validation - V3.1 Exploit -
file_put_contents("logs/error_" . $_POST['email'] . ".log", $error); An attacker injects:
// Additional header injection cleanup $email = str_replace(array("\r", "\n", "%0a", "%0d"), '', $email); If you must, use mb_encode_mimeheader() or a safe wrapper. Step 4: Disallow null bytes and control characters. if (preg_match('/[\x00-\x1F\x7F]/', $input)) http_response_code(400); exit("Invalid characters"); php email form validation - v3.1 exploit
attacker@example.com CC: victims@example.com Once the regex is bypassed, the script passes the unsanitized $_POST['email'] directly to the mail() function's $extra_headers parameter or the $to parameter with improper escaping. file_put_contents("logs/error_"
