Clientless Attack

1. PMKID (Pairwise Master Key Identifier) handshake attacks are a specific type of attack targeting WiFi networks that use WPA/WPA2-PSK (Pre-Shared Key) security protocols. PMKID is part of the process for establishing a secure connection between a client device and an access point (AP).

   

1. Overview of PMKID Handshake:

   1. Purpose: PMKID is used in WPA/WPA2-PSK to derive the Pairwise Transient Key (PTK) for securing communications between a client device and an AP.

   2. PMKID Generation:

      • When a client attempts to connect to an AP using a pre-shared key (PSK), the AP sends a PMKID to the client after successful authentication.

      • The client then verifies the PMKID with its own calculation to ensure both devices derive the same PTK for encryption.

   PMKID Handshake Attack:

   1. Attack Method:

      • Capture PMKID: An attacker captures the PMKID during the initial connection attempt between a client and an AP. This can be achieved passively by sniffing WiFi traffic.

   2. Tools Used: Attackers often use tools such as hcxdumptool, hcxpcaptool, or hashcat to capture and process PMKID information.

   3. Objective: The primary objective of capturing PMKID is to launch offline brute-force attacks against the PSK to recover the WiFi network’s passphrase.

   4. Brute-Force Attack:

      • Once the PMKID is captured, attackers use powerful computing resources and password-cracking techniques to guess the PSK through brute-force or dictionary attacks.

      • This process involves trying multiple combinations of passwords until the correct one is found that matches the PMKID.

   Mitigation Strategies:

   To defend against PMKID handshake attacks, consider implementing these mitigation strategies:

   • Use Strong and Complex PSKs: Choose a PSK that is long, random, and difficult to guess or crack.

   • Enable WPA3: Transition to WPA3 if supported, as it provides enhanced security features and mitigates vulnerabilities associated with WPA/WPA2-PSK.

   • Monitor WiFi Traffic: Continuously monitor WiFi networks for unusual activity or unauthorized devices capturing PMKIDs.

   • Update Firmware: Keep APs and client devices updated with the latest firmware to patch known vulnerabilities.

   • Intrusion Detection Systems (IDS): Deploy IDS to detect and alert on suspicious activities related to PMKID capture attempts.

   • Network Segmentation: Segment networks and apply access controls to limit the impact of compromised devices.

   By implementing these measures, organizations can strengthen their defenses against PMKID handshake attacks and enhance the overall security of their WiFi networks.