Bruteforcing WPA2 with Hashcat & GPU Power

Introduction

So far, you’ve learned to capture WPA2 handshakes and crack them using aircrack-ng and wordlists. But aircrack is CPU-bound — and slow. When speed matters, it’s time to unleash Hashcat with GPU acceleration.

Hashcat is the king of password cracking tools, known for its efficiency, customizability, and insane speed — especially when using modern GPUs.

🔍 Why Use Hashcat Over Aircrack-ng?

Feature	Aircrack-ng	Hashcat
Speed	CPU-based (slow)	GPU-based (fast)
Algorithm Support	Limited	Extensive
Wordlist Attacks	✅	✅
Rule-based Cracking	❌	✅
Mask Attacks	❌	✅
Distributed Cracking	❌	✅

⚙️ Requirements

A captured WPA2 handshake (.cap file)
A system with a compatible GPU (NVIDIA or AMD)
Installed drivers & Hashcat
Wordlist or masks

NOTE: Kali Linux may not be ideal for GPU cracking. Consider Windows, Ubuntu, or a separate cracking rig for heavy jobs.

Step-by-Step: Bruteforcing WPA2 with Hashcat

1. Convert Handshake to Hashcat Format

Hashcat doesn’t accept .cap files directly. You need to convert them to .hccapx format using cap2hccapx:

git clone https://github.com/hashcat/hashcat-utils.git
cd hashcat-utils/src
make
./cap2hccapx.bin handshake.cap handshake.hccapx

Alternatively, use the online converter:
https://hashcat.net/cap2hccapx/

2. Install & Run Hashcat

If Hashcat isn’t installed, use:

sudo apt install hashcat

Or download manually from:
https://hashcat.net/hashcat

3. Run a Wordlist Attack

Once you have the .hccapx file, run Hashcat with a wordlist:

hashcat -m 2500 -a 0 handshake.hccapx /path/to/wordlist.txt

Explanation:

-m 2500: WPA/WPA2 hash mode
-a 0: Dictionary attack mode
handshake.hccapx: Converted handshake file
/path/to/wordlist.txt: Your wordlist (e.g., rockyou.txt)

If successful, Hashcat will output something like:

<network_mac>:<client_mac>:password123

4. Advanced: Mask Attack (If You Know the Pattern)

If you suspect the password follows a pattern, you can use a mask attack.
Example: Try all 8-digit numeric PINs:

hashcat -m 2500 -a 3 handshake.hccapx ?d?d?d?d?d?d?d?d

Note:

?d = digit (0–9)

This is very effective for PIN-based or predictable passwords.

Legal Warning

As always, cracking WPA2 is only legal in a controlled environment or with explicit permission. Misusing these tools is a criminal offense in most jurisdictions.

Wrapping Up

Using Hashcat with GPU acceleration unlocks next-level power for bruteforcing WPA2 passwords. It’s a must-have in every wireless pentester’s toolbox.

Next up:
🧬 Part 9 – PMKID Attack: Crack WPA2 Without Even a Handshake

A more modern, stealthy method that doesn’t need any clients connected.