A stock checker that pings an IP. A comment box that echoes your name. These simple features hide a terrifying truth: they might be executing your commands on the server. Learn to spot, test, and weaponize RCE — the ultimate bug bounty prize.
Welcome back. You’ve mastered XXE, SSRF, and IDOR. Now we reach the holy grail of web vulnerabilities: Remote Command Execution (RCE) . This is the vulnerability where you can make the server run operating system commands of your choice. RCE can come from command injection (directly injecting into a system call) or code injection (injecting PHP, Python, or other interpreted code). The impact? Full server compromise — data theft, backdoors, pivoting to internal networks, and sometimes complete control of the cloud environment. This guide will show you how to find RCE, what commands to test safely, and how to report it for maximum reward.
The Core Idea: When the Application Calls Out to the OS
Many web applications interact with the underlying operating system. For example:
- A stock checker might run a command like
stocklookup 5141to get inventory. - A network diagnostic tool might…