What is a MachineAccount and where is its password stored?

A MachineAccount is the default computer account created when a Windows system is installed. Its password hash is locally stored in the registry at `HKLM\SECURITY\Policy\Secrets\$machine.ACC`. If the computer joins a domain, the hash is also synchronized to the domain controller and saved in the NTDS.dit file. By default, the password is automatically changed every 30 days, making plaintext recovery difficult. For more on extracting hashes from the registry, see Penetration Basics - Brute-Forcing Domain User Passwords via LDAP Protocol (though that article focuses on LDAP, similar registry extraction methods apply).