Subscribe User bug

How it was found

Hi Hubdia,

i found a bug in your subscribe page (https://hubdia.com/) which this bug can subscribe multiple emails.

Vulnerable Link: https://hubdia.com/

Proof of Concept:

1. use Live HTTP Headers (firefox addon)
2. change the email (see in attached photo)
3. submit the request in many times

Thanks, Jerold Camacho