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

# CrossFit

> Writeups verificados de la máquina CrossFit de Hack The Box

# CrossFit

<p className="machine-summary"><span className="prompt"><code>\$ tldr</code></span> XSS + CSRF bypass → webshell lftp → cron php-shellcommand</p>

<div className="machine-meta">
  | ·                 | ·                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
  | ----------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
  | Sistema operativo | Linux                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
  | Dificultad        | Insano                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
  | Vector            | <span className="vbadge vbadge-web">Web</span>                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
  | IP                | `10.10.10.208`                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
  | Fecha de retirada | 2021-03-20                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
  | Skills            | FTP SSL Certificate Enumeration XSS Injection Subdomain Enumeration through the Origin Header \[Access-Control-Allow-Origin] Accessing internal websites through XSS - Creating a javascript file Registering a new user through XSS - CSRF Protection Bypass Uploading a webshell with lftp Cracking Hashes Abusing Cron Job php-shellcommand exploitation - escapeArgs option is not working properly Injecting data into the database to achieve remote command execution (RCE) \[User Pivoting] Binary Analysis - dbmsg \[GHIDRA] Reversing Creating an exploit - Abusing Rand \[Time travel] Abusing symbolic links Injecting our own public key as authorized\_keys in /root |
</div>

## Writeups

| Idioma  | Autor       | Formato | Enlace                                                       |
| ------- | ----------- | ------- | ------------------------------------------------------------ |
| 🇪🇸 ES | **S4vitar** | Vídeo   | [Abrir](https://www.youtube.com/watch?v=sIaVrGnzRjM)         |
| 🇬🇧 EN | **0xdf**    | Texto   | [Abrir](https://0xdf.gitlab.io/2021/03/20/htb-crossfit.html) |
| 🇬🇧 EN | **IppSec**  | Vídeo   | [Abrir](https://www.youtube.com/watch?v=Z3Lj_YN0crc)         |

## Recursos por skill

Documentación curada para cada técnica que aparece en la columna *Skills* de arriba. Fuentes: HackTricks, GTFOBins, PortSwigger, etc.

| Skill                             | Fuente      | Enlace                                                                                                             |
| --------------------------------- | ----------- | ------------------------------------------------------------------------------------------------------------------ |
| Subdomain Enumeration             | HackTricks  | [Abrir](https://book.hacktricks.wiki/en/generic-methodologies-and-resources/external-recon-methodology/index.html) |
| Cracking Hashes (hashcat / John)  | HackTricks  | [Abrir](https://book.hacktricks.wiki/en/generic-methodologies-and-resources/brute-force.html)                      |
| Port Forwarding / Pivoting        | HackTricks  | [Abrir](https://book.hacktricks.wiki/en/generic-hacking/tunneling-and-port-forwarding.html)                        |
| CSRF (Cross-Site Request Forgery) | PortSwigger | [Abrir](https://portswigger.net/web-security/csrf)                                                                 |
| Remote Code Execution (RCE)       | HackTricks  | [Abrir](https://book.hacktricks.wiki/en/pentesting-web/command-injection.html)                                     |
| Cross-Site Scripting (XSS)        | HackTricks  | [Abrir](https://book.hacktricks.wiki/en/pentesting-web/xss-cross-site-scripting/index.html)                        |
| Cross-Site Scripting (XSS)        | PortSwigger | [Abrir](https://portswigger.net/web-security/cross-site-scripting)                                                 |

## Skills relacionadas que conviene dominar

Brute Force / Rate-Limit Bypass · Local File Inclusion (LFI) · Remote File Inclusion (RFI) · Shellshock (CVE-2014-6271) · SQL Injection · Server-Side Request Forgery

## Si te gustó esta máquina, prueba

* [Stacked](/htb/machines/linux/insano/stacked) — Linux, Insano
* [Joker](/htb/machines/linux/dificil/joker) — Linux, Difícil
* [Schooled](/htb/machines/linux/medio/schooled) — Linux, Medio
* [Undetected](/htb/machines/linux/medio/undetected) — Linux, Medio
* [Meta](/htb/machines/linux/medio/meta) — Linux, Medio

***

## Comentarios y truquillos

¿Algo no funcionó del writeup oficial? ¿Has encontrado un truco mejor? Compártelo aquí — los comentarios viven en [GitHub Discussions](https://github.com/FFuson/HTB_Writeups/discussions).

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

*Última actualización: 2026-06-07*

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