Form with POST method in an email?

Question

I send emails to my clients with an "Answer survey" link, and I'm not sure what HTTP method to use to add the user's email to each link, my options are to use the email as a GET parameter in the URL or to add a form to the email with the user's email as a POST parameter.

What is the pros/cons of each ? and what is the best way to accomplish this? I'm concerned about security.

You cannot place forms in email therefore - no, it's not possible to send POST request from email. What's not safe about using GET? — Jakub Matczak, May 05 '17 at 08:37
You can use the get with an encrypted value then decrypt the value in your page — Pete, May 05 '17 at 08:38
@JakubMatczak User can just change parameters on url and answer for other ppl — Sydowh, May 05 '17 at 08:43
The user can also easily modify POST request. There's no real difference in security. — Jakub Matczak, May 05 '17 at 08:44
http://stackoverflow.com/questions/198462/is-either-get-or-post-more-secure-than-the-other — Ahmed Ginani, May 05 '17 at 08:46

score 1 · Answer 1 · edited May 05 '17 at 08:49

You cannot post post in email also javascript will not run email client , the best why is to make the secure email link for that you need to encrypt the email and put that in link

like that http://{link-to-surveypage}/{encrypt-email}

on that page you decrypt that and get the user email in safe and secure why here is the function you can use

<?php
function encrypt_decrypt($action, $string)
{
    $output = false;

    $key = 'P0Qst@163!#';

    // initialization vector 
    $iv = md5(md5($key));

    if ($action == 'encrypt') {
        $output = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, md5($key), $string, MCRYPT_MODE_CBC, $iv);
        $output = base64_encode($output);
    } else {
        if ($action == 'decrypt') {
            $output = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, md5($key), base64_decode($string), MCRYPT_MODE_CBC, $iv);
            $output = rtrim($output, "");
        }
    }
    return $output;
}

The `mcrypt` extension is deprecated from PHP 7.1, it's not advisable to write code using it any more. You should be using the [OpenSSL](http://php.net/manual/en/book.openssl.php) library instead. — iainn, May 05 '17 at 08:53

Form with POST method in an email?

1 Answers1