Unlocking Hidden Paths: Web Fuzzing with FFUF

 

Introduction

When performing penetration tests or bug bounty hunting, uncovering hidden directories, files, and parameters can lead to serious vulnerabilities.
This is where ffuf (Fuzz Faster U Fool) comes into play — a fast and flexible web fuzzer that every hacker should have in their toolkit.

In this article, we’ll dive deep into how I use ffuf to discover hidden gems on a web application, escalate findings, and why it’s one of my favorite recon tools.

 

Why FFUF?

FFUF is a favorite among security professionals because:

• Fast and Efficient:
  Written in Go, it’s designed for speed. It can handle thousands of requests quickly without slowing down.
• Flexible Usage:
  FFUF isn’t just for directory brute-forcing. It can also fuzz:

URL paths,GET/POST parameters,HTTP headers

Subdomains (Virtual Hosts)

• Easy to Automate:
  Its simple command-line style makes it great for automation and adding to scripts during reconnaissance.

Setting the Stage

• Install ffuf:

sudo apt install ffuf
# OR
go install github.com/ffuf/ffuf/v2@latest

• Basic Usage Example:

ffuf -u https://target.com/FUZZ -w /path/to/wordlist.txt

This will fuzz the target URL by replacing FUZZ with each entry from your wordlist.

Real Pentest Example

Goal:

Find hidden admin panels on a test target (example: https://targetsite.com)

(Note: Replace targetsite.com with your real authorized target during an actual pentest.)

Step 1: Directory Fuzzing

We want to discover hidden admin panels.
We start by fuzzing directories using a common wordlist.

ffuf -u https://targetsite.com/FUZZ -w /usr/share/wordlists/dirbuster/directory-list-2.3-medium.txt -fc 404

• -u → Target URL (FUZZ will be replaced by words from the list)
• -w → Wordlist for directories
• -fc 404 → Filter out "Not Found" pages

Step 2: Analyzing Results

After running ffuf, you might find results like:

/admin          [Status: 301, Size: 178]
/login          [Status: 200, Size: 350]
/dashboard      [Status: 403, Size: 280]

• /admin redirected → possible admin panel
• /login available → login page detected
• /dashboard forbidden → might be something sensitive

Step 3: Digging Deeper

We can also fuzz deeper inside /admin/:

ffuf -u https://targetsite.com/admin/FUZZ -w /usr/share/wordlists/dirbuster/directory-list-2.3-medium.txt -fc 404

• Sometimes hidden pages like /admin/backup/ or /admin/settings/ show up here!

Pro Tips

• Use extensions: Fuzz for .php, .bak, .zip, .old, etc.

ffuf -u https://targetsite.com/FUZZ -w common.txt -e .php,.bak,.zip

• Filter Noise:
  Use -fc, -fs, -fw to filter codes, size, or words and avoid junk.
• ClusterBomb Technique:
  Fuzz multiple points by chaining.
• Automate with Bash:
  Add ffuf to recon scripts for passive discovery.

Conclusion

FFUF is not just another fuzzer — it’s a weapon when used smartly.
From initial reconnaissance to post-exploitation fuzzing, it consistently helps me find paths others miss.

Whether you’re a pentester, a CTF player, or a bug bounty hunter, mastering FFUF gives you a serious edge.

Happy Fuzzing!