Overpass-the-Hash and Token Impersonation
Overpass-the-Hash converts an NTLM hash into a Kerberos ticket and uses that ticket to authenticate to services that require Kerberos rather than NTLM. Token impersonation reuses tokens from processes already running as other users on the same host to move into their identity context. Both techniques build on credentials or tokens already present in memory rather than needing new credential material.
Overpass-the-Hash
Standard Pass-the-Hash works over NTLM. In environments where NTLM is disabled or blocked for certain services, you need a Kerberos TGT instead. Overpass-the-Hash takes an NT hash and requests a real TGT from the domain controller using that hash as the key.
Token impersonation for lateral movement
Windows access tokens represent the security context of a process or thread. If a privileged user has a process running on the host you control, you can duplicate their token and run commands in their context without needing their credentials. This requires SeImpersonatePrivilege or SeAssignPrimaryTokenPrivilege, or local admin access.
Finding tokens worth stealing
Before impersonating, identify which valuable accounts have processes running on the current host.
Make-Token — creating tokens from credentials
If you have plaintext credentials for an account but are running under a different identity, you can create a new logon session with those credentials without spawning a new process.
Token impersonation as a privilege escalation technique from a low-privilege service account is covered in Windows Access Token Manipulation for Privilege Escalation. For using the acquired Kerberos tickets for persistence beyond their natural lifetime see Golden and Silver Ticket Persistence.
References
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Rubeus — GhostPack GitHubgithub.com/GhostPack/Rubeus (opens in new tab)
asktgt, ptt, and Kerberos ticket operations
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mimikatz — GitHubgithub.com/gentilkiwi/mimikatz (opens in new tab)
sekurlsa::pth and token manipulation reference
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