> ## Documentation Index
> Fetch the complete documentation index at: https://rootea.es/llms.txt
> Use this file to discover all available pages before exploring further.

# Fulcrum

> Verified writeups for the Fulcrum machine of Hack The Box

# Fulcrum

<p className="machine-summary"><span className="prompt"><code>\$ tldr</code></span> API enum → XXE avanzado → SSRF → RFI/RCE → PSCredential decrypt</p>

<div className="machine-meta">
  | ·                | ·                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
  | ---------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
  | Operating system | Linux                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
  | Difficulty       | Insane                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
  | Vector           | <span className="vbadge vbadge-ad">Active Directory</span>                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
  | 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) |
</div>

## Writeups

| Language | Author      | Format | Link                                                       |
| -------- | ----------- | ------ | ---------------------------------------------------------- |
| 🇪🇸 ES  | **S4vitar** | Vídeo  | [Open](https://www.youtube.com/watch?v=O8-l2KNeRkM)        |
| 🇬🇧 EN  | **0xdf**    | Texto  | [Open](https://0xdf.gitlab.io/2022/05/11/htb-fulcrum.html) |
| 🇬🇧 EN  | **IppSec**  | Vídeo  | [Open](https://www.youtube.com/watch?v=46RJxJ-Fm0Y)        |

## 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](https://book.hacktricks.wiki/en/pentesting-web/file-inclusion/index.html)                   |
| XML External Entity             | HackTricks | [Open](https://book.hacktricks.wiki/en/pentesting-web/xxe-xee-xml-external-entity.html)            |
| Information Leakage             | HackTricks | [Open](https://book.hacktricks.wiki/en/pentesting-web/information-leak.html)                       |
| Active Directory                | HackTricks | [Open](https://book.hacktricks.wiki/en/windows-hardening/active-directory-methodology/index.html)  |
| Brute Force / Rate-Limit Bypass | HackTricks | [Open](https://book.hacktricks.wiki/en/generic-methodologies-and-resources/brute-force.html)       |
| Port Forwarding / Pivoting      | HackTricks | [Open](https://book.hacktricks.wiki/en/generic-hacking/tunneling-and-port-forwarding.html)         |
| Server-Side Request Forgery     | HackTricks | [Open](https://book.hacktricks.wiki/en/pentesting-web/ssrf-server-side-request-forgery/index.html) |
| Remote Code Execution (RCE)     | HackTricks | [Open](https://book.hacktricks.wiki/en/pentesting-web/command-injection.html)                      |

## 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](/en/htb/machines/linux/dificil/kotarak) — Linux, Hard
* [MultiMaster](/en/htb/machines/windows/insano/multimaster) — Windows, Insane
* [Sniper](/en/htb/machines/windows/medio/sniper) — Windows, Medium
* [Quick](/en/htb/machines/linux/dificil/quick) — Linux, Hard
* [Talkative](/en/htb/machines/linux/dificil/talkative) — Linux, Hard

***

## Comments & tips

Did the official writeup not work? Found a smarter trick? Share it here — comments live in [GitHub Discussions](https://github.com/FFuson/HTB_Writeups/discussions).

<div className="rootea-giscus-wrap" data-giscus-term="machine:fulcrum" data-giscus-lang="en" />

*Last updated: 2026-06-07*

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