Fulcrum

Verified writeups for the Fulcrum machine of Hack The Box

Fulcrum

$ tldr API enum → XXE avanzado → SSRF → RFI/RCE → PSCredential decrypt

·	·
Operating system	Linux
Difficulty	Insane
Vector	Active Directory
IP	10.10.10.62
Retirement date	2022-05-11
Skills	API Enumeration - Endpoint Brute Force Advanced XXE Exploitation (XML External Entity Injection) XXE - Custom Entities XXE - External Entities XXE - XML Parameter Entities XXE - Blind SSRF (Exfiltrate data out-of-band) + Base64 Wrapper [Reading Internal Files] XXE + RFI (Remote File Inclusion) / SSRF to RCE Host Discovery - Bash Scripting Port Discovery - Bash Scripting Decrypting PSCredential Password with PowerShell PIVOTING 1 - Tunneling with Chisel + Evil-WinRM Gaining access to a Windows system PowerView.ps1 - Active Directory Users Enumeration (Playing with Get-DomainUser) Information Leakage - Domain User Password PIVOTING 2 - Using Invoke-Command to execute commands on another Windows server Firewall Bypassing (Playing with Test-NetConnection in PowerShell) - DNS Reverse Shell Authenticating to the DC shares - SYSVOL Enumeration Information Leakage - Domain Admin Password PIVOTING 3 - Using Invoke-Command to execute commands on the Domain Controller (DC)

Writeups

Language	Author	Format	Link
🇪🇸 ES	S4vitar	Vídeo	Open
🇬🇧 EN	0xdf	Texto	Open
🇬🇧 EN	IppSec	Vídeo	Open

Skill resources

Curated documentation for each technique listed in the Skills column above. Sources: HackTricks, GTFOBins, PortSwigger, etc.

Skill	Source	Link
Remote File Inclusion (RFI)	HackTricks	Open
XML External Entity	HackTricks	Open
Information Leakage	HackTricks	Open
Active Directory	HackTricks	Open
Brute Force / Rate-Limit Bypass	HackTricks	Open
Port Forwarding / Pivoting	HackTricks	Open
Server-Side Request Forgery	HackTricks	Open
Remote Code Execution (RCE)	HackTricks	Open

Related skills worth mastering

Local File Inclusion (LFI) · Kerberoasting · AS-REP Roasting · DCSync · BloodHound · Group Policy Preferences (GPP) · GetNPUsers (Impacket) · Cross-Site Scripting (XSS)

If you liked this machine, try

• Kotarak — Linux, Hard
• MultiMaster — Windows, Insane
• Sniper — Windows, Medium
• Quick — Linux, Hard
• Talkative — Linux, Hard

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Last updated: 2026-06-07