Pass the Certificate
Theory
The Kerberos authentication protocol works with tickets in order to grant access. An ST (Service Ticket) can be obtained by presenting a TGT (Ticket Granting Ticket). That prior TGT can only be obtained by validating a first step named "pre-authentication" (except if that requirement is explicitly removed for some accounts, making them vulnerable to ASREProast). The pre-authentication can be validated symmetrically (with a DES, RC4, AES128 or AES256 key) or asymmetrically (with certificates). The asymmetrical way of pre-authenticating is called PKINIT.
Pass the Certificate is the fancy name given to the pre-authentication operation relying on a certificate (i.e. key pair) to pass in order to obtain a TGT. This operation is often conducted along shadow credentials, AD CS escalation and UnPAC-the-hash attacks.
Keep in mind a certificate in itself cannot be used for authentication without the knowledge of the private key. A certificate is signed for a specific public key, that was generated along with a private key, which should be used when relying on a certificate for authentication.
The "certificate + private key" pair is usually used in the following manner
PEM certificate + PEM private key
PFX certificate export (which contains the private key) + PFX password (which protects the PFX certificate export)
Practical
Evil-Winrm
For this attack you need to have access the .pfx file.
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