Mimikatz

Mimikatz is a powerful open-source tool primarily used for extracting plaintext passwords, password hashes, Kerberos tickets, and other sensitive authentication data from Windows systems. Developed by Benjamin Delpy, it is often used by penetration testers and malicious actors alike due to its capabilities.

Key Features of Mimikatz:

1. Credential Extraction:

   • Plaintext Passwords: Mimikatz can retrieve passwords stored in memory by accessing the Local Security Authority (LSA).
   • NTLM Hashes: It can extract password hashes used for NTLM authentication.
   • Kerberos Tickets: Mimikatz can dump Kerberos tickets (TGTs and TGSs) and even perform ticket granting requests.

2. Password Cracking:

   • Mimikatz can be used in conjunction with tools like Hashcat to crack extracted password hashes.

3. Pass-the-Hash and Pass-the-Ticket:

   • Mimikatz enables attackers to use stolen hashes or tickets to authenticate without needing to know the actual passwords, facilitating lateral movement within a network.

4. Overpass-the-Hash:

   • This technique allows an attacker to create a Kerberos ticket using an NTLM hash, allowing access without the actual password.

5. Module Support:

   • Mimikatz supports various modules that extend its functionality, such as targeting specific Windows features or authentication mechanisms.

Usage Scenarios:

• Penetration Testing: Ethical hackers use Mimikatz to test the security of networks by demonstrating how easily credentials can be extracted and exploited.
• Malicious Attacks: Cybercriminals may use Mimikatz to perform credential dumping as part of a broader attack strategy.

Detection and Mitigation:

1. Monitoring: Use endpoint detection and response (EDR) solutions to monitor for suspicious activity that may indicate Mimikatz usage, such as unusual access to LSASS (Local Security Authority Subsystem Service).

2. Access Controls: Limit user permissions and employ least privilege principles to reduce the risk of unauthorized access to sensitive processes.

3. Patch Management: Regularly update Windows systems and apply security patches to protect against vulnerabilities that Mimikatz might exploit.

4. Defensive Tools: Implement security features like Credential Guard, which helps protect against credential theft by isolating LSA.

5. User Education: Train users on the importance of password security, including the use of strong, unique passwords and awareness of phishing attacks.