Index.php is the landing page of your PrestaShop store. Hence, no doubt, this is one of the most visited pages of your website. However, this also implies that index.php is actively targeted by attackers. If the attackers are successful in compromising index.php of your Prestashop site, the results can be disastrous. The attackers can use it to serve malware, deface your site or steal credit card info of the customers of your PrestaShop store.