HackTheBox: Optimum - HFS RCE & Kernel Exploit Privesc

Introduction Optimum is a Windows machine on HackTheBox that features a vulnerable HttpFileServer application and privilege escalation through kernel exploitation. This box teaches the importance of checking software versions and using enumeration tools to find the right kernel exploit. Difficulty: Easy OS: Windows Skills: Version-based exploitation, kernel exploit enumeration, Windows privilege escalation Reconnaissance Nmap Scan nmap -sC -sV -oN nmap/optimum 10.129.2.30 Port Service Version 80 HTTP HttpFileServer 2.3 Only one port open running HFS 2.3 (HttpFileServer). When we see specific software with version numbers, we immediately check for known exploits. ...

February 21, 2026 · 4 min