# File Upload Vulnerabilities

> Master file upload vulnerabilities. Learn to bypass client-side validation, extension filters, and magic bytes to achieve Remote Code Execution (RCE) via web shells.

Canonical: https://codelivly.com/rooms/file-upload-vulnerabilities
Last updated: 2026-07-29

| | |
|---|---|
| Level | Intermediate |
| Category | Cybersecurity |
| Lessons | 6 |
| Estimated time | 30 min |
| XP | 200 |

A comprehensive module covering the critical security flaws in web application file upload mechanisms. Explore how to bypass client-side validation, manipulate file extensions and MIME types, and evade magic byte checks. Learn to upload and execute malicious web shells for Remote Code Execution (RCE), complete with a guided lab to solidify your exploitation skills.

## Lessons

1. What is a File Upload Vulnerability & Its Impact (30 min)
2. Bypassing Client-Side Validation (30 min)
3. Extension & MIME Type Bypass Techniques (30 min)
4. Uploading Web Shells for Remote Code Execution (30 min)
5. Magic Bytes & Content Sniffing Bypass (30 min)
6. File Upload RCE Lab Guide (30 min)

## Related

- [Learning path: Web Application Security](https://codelivly.com/learning-paths/web-application-security)
- [All rooms](https://codelivly.com/rooms)