HTB: Markup - OSCP Prep Write-up

Markup is done. A Very Easy Windows box, but with a solid lesson on XXE injection - from discovering the vulnerability to weaponizing it for file read and SSH key extraction. Clean privesc through AutoLogon credentials found by WinPEAS. Machine info Name Markup Platform HackTheBox OS Windows Difficulty Very Easy TL;DR Login with default credentials admin:password Order form submits XML - vulnerable to XXE injection XXE with PHP wrapper to read process.php source and confirm the vulnerability Extract Daniel’s SSH private key via XXE WinPEAS finds AutoLogon credentials for Administrator Recon RustScan + Nmap 1 rustscan -a 10.129.95.192 -- -sV -sC -Pn -A ...

April 19, 2026 · 3 min · João Vítor Bonin