WPA2 Pen Testing Without Monitor Mode

TL;DR

Pen testing WPA2 networks without a monitor mode capable adapter is tricky, but possible. It relies on passive attacks like dictionary/brute-force attempts against the handshake using tools that don’t directly capture packets in monitor mode, or exploiting WPS vulnerabilities if enabled. Success rates are lower than with monitor mode, and it’s generally slower. This guide covers practical methods.

Understanding the Limitations

Most effective WPA2 pen testing relies on capturing a four-way handshake using an adapter in monitor mode. Without this, you’re limited to:

• Dictionary/Brute-Force Attacks: Trying common passwords or generating combinations.
• WPS Exploitation: If WPS is enabled (very common on older routers), it can be cracked relatively easily.
• Evil Twin Attacks (Limited): Can work, but require client connection and are less reliable without monitor mode for initial handshake capture.

These methods are slower and less reliable than capturing a handshake directly.

Step-by-Step Guide

1. Check WPS Status: First, determine if the target network has WPS enabled.
   • Use Wifite (requires Python and some dependencies) to scan for WPS-enabled networks. It will automatically identify them.
   • Alternatively, use Reaver directly:

     reaver -i wlan0 -b [target_BSSID] -vv

     (Replace wlan0 with your wireless interface and [target_BSSID] with the router’s MAC address.)

2. Exploit WPS (If Enabled): If WPS is enabled, Reaver is your best bet.
   • Run Reaver again with the same command as above. It will attempt to crack the WPS PIN. This can take several hours depending on the router and PIN complexity.

   • reaver -i wlan0 -b [target_BSSID] -vv

3. Dictionary/Brute-Force Attack (If WPS is Disabled): This requires capturing *some* form of network traffic, even if it’s not a full handshake.
   • Aircrack-ng Suite: While you can’t use monitor mode directly, Aircrack-ng still has tools for cracking captured data.
   • Capture Traffic (Limited): Use Airodump-ng to passively capture 802.11 traffic, even without monitor mode. The amount of useful data captured will be limited.

     airodump-ng wlan0

   • Hashcat/John the Ripper: Use Hashcat or John the Ripper to crack any captured WPA2 handshakes (even partial ones) against a wordlist. This is unlikely to succeed with limited data.

     hashcat -m 2500 [capture_file.cap] ?a?a?a?a?a?a [wordlist.txt]

4. Evil Twin Attack (Advanced, Limited): This involves creating a fake access point with the same SSID as the target network.
   • Use Hostapd to create the rogue AP.
   • Configure Hostapd to use the target’s SSID and channel.
   • Clients may connect to your fake AP, allowing you to capture a handshake (though this is less reliable without monitor mode for initial beaconing).
5. Consider Using a USB Adapter: If possible, the easiest solution is to purchase an inexpensive USB Wi-Fi adapter that supports monitor mode. This significantly improves your chances of success.

Important Considerations

• Legality: Always obtain explicit permission before pen testing any network. Unauthorized access is illegal.
• Wordlists: Use strong, comprehensive wordlists for dictionary attacks.
• Time: These methods can take a very long time to complete, especially brute-force attacks.
• Router Security: Modern routers are generally more secure and harder to crack without monitor mode capabilities.