calc.php

MediumWeb Security

Overview

This is my very simple calculator. Can you calculate what happens if we multiply the flag in /[random]_flag.txt with 5 ?

Flag Format: Flag{}

Lab Details

Prerequisites & Requirements

  • Basic understanding of PHP programming language
  • Familiarity with web application vulnerabilities
  • Knowledge of HTTP methods (GET, POST)
  • Basic command-line experience

What will you learn?

  • Remote Code Execution (RCE) via PHP's eval() function
  • Bypassing input validation and WAF (Web Application Firewall) restrictions
  • XOR encoding techniques for payload obfuscation
  • PHP execution operators and shell command execution

Tools

  • Web Browser
  • Python 3
  • Text editor

Job Positions

Penetration Tester

Tags

PhpLfiInput ValidationWaf BypassSource Code Review