loading . . . HTB: DarkCorp DarkCorp lives up to it’s insane difficulty, with three hosts, including a Windows AD domain, and starts with a Debian web/mail server. I’ll exploit an XSS in RoundCube to get access to the admin’s emails, leaking a private subdomain. I’ll reset the admin’s password and get into the dashboard, identifying an SQLI. I’ll abuse PostgreSQL to get RCE from this two ways. In a PGP-encrypted backup I’ll find the hash for another user and crack it, getting auth to the domain. Those creds also get me into a website on the Windows web server that can do status checks on other websites. These checks will attempt NTLM authentication, and I’ll relay that to create a domain entry, and then use printer bug to get the WEB-01 box to authenticate to me, which I can relay to get a silver ticket for administrator on WEB-01. On that host I’ll find the local administrator account creds in the scheduled tasks, and use those to decrypt a stored credential. Password spraying that password will own another account on the domain. That user can get a shadow credential for another user. That user has a matching .adm account, and I’ll do UPN spoofing to get access to that admin account back on the original Linux host. With root access on that host, I’ll pull cached AD credentials from the SSSD database to pivot back to the DC. This user can modify a GPO, which I’ll abuse to get administrator access over the entire domain. https://0xdf.gitlab.io/2025/10/18/htb-darkcorp.html