Pass-the-hash attack (PtH) is
|“||a hacking technique that allows an attacker to authenticate to a remote system by using the underlying hash of a user's password rather than having to know the actual password itself.||”|
"Hackers generally use hashes from the current machine to springboard to other machines, grabbing higher privileged credentials as they progress. A range of security measures are required to fully mitigate all the facets of Pass-the-Hash. One scalable and highly effective mitigation involves limiting workstation-to-workstation communication, thereby thwarting an attacker's ability to leverage PtH to move laterally within the network."