A Puzzling Backdoor Upload
<p>After a successful compromise, backdoors are frequently left behind and function as a point of re-entry into the website environment. These malicious pieces of code are a valuable tool for attackers and allow them to bypass any existing access controls into the web server environment.</p>
To demonstrate just how common this malware is, in 2017 we identified that 71% of all compromises seen by Sucuri had a PHP-based backdoor hidden within the site.