Hashcat: Crack 8-Character Uppercase Wifi Passwords

G5 Cyber Security

2 weeks ago

TL;DR

This guide shows you how to crack an 8-character uppercase WiFi password using Hashcat. It assumes you have the WiFi handshake (.cap file) and know the password consists only of uppercase letters (A-Z).

Prerequisites

Hashcat: Download and install Hashcat from https://hashcat.net/
WiFi Handshake (.cap file): Capture the WiFi handshake using a tool like Aircrack-ng or similar.
GPU: Hashcat performs best with a powerful GPU.

Step-by-step Guide

Identify the Hash Type: Determine the hash type used by your WiFi network. Common types include WPA, WPA2, and WPA3. You can often find this information in the output of your handshake capture tool or through online resources based on your router model. For example, if you’re using Aircrack-ng, the output will show the hash type (e.g., `[WPA]`).
Prepare the Wordlist: Since we know the password is 8 uppercase characters, we’ll generate a wordlist containing all possible combinations of uppercase letters. Hashcat can do this for us.
```
hashcat -m  --wordlists /dev/null -a 3 -w 8 ?u?u?u?u?u?u?u?u > wordlist.txt
```
Replace `` with the actual hash type identified in Step 1 (e.g., `0` for WPA, `1` for WPA2). This command creates a file named wordlist.txt containing all possible 8-character uppercase combinations.
Run Hashcat: Now we’ll use Hashcat to crack the password using the generated wordlist and the captured handshake file.
```
hashcat -m  -a 0  wordlist.txt --force
```
Replace `` with the hash type (e.g., `0` for WPA, `1` for WPA2) and with the name of your handshake file.
The --force option is used to bypass warnings about potentially slow cracking speeds.
Monitor Progress: Hashcat will display progress information on the screen, including the current cracking speed (hashes per second). The time it takes to crack the password depends on your GPU’s performance and the complexity of the hash.
Retrieve the Password: If Hashcat successfully cracks the password, it will be displayed in the output window.
```
[!] Cracked password: YOUR_PASSWORD
```

Important Considerations

Legal Implications: Cracking WiFi passwords without permission is illegal. This guide is for educational purposes only and should be used responsibly.
Hash Type Accuracy: Ensure you’ve correctly identified the hash type. Using the wrong hash type will result in incorrect cracking attempts.
Resource Intensive: Password cracking can be very resource intensive, especially with longer passwords or more complex character sets.