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

# Epsilon

> Verified writeups for the Epsilon machine of Hack The Box

# Epsilon

<p className="machine-summary"><span className="prompt"><code>\$ tldr</code></span> Git leak → AWS Lambda enum → JWT bypass → SSTI → tar symlink</p>

<div className="machine-meta">
  | ·                | ·                                                                                                                                                                              |
  | ---------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
  | Operating system | Linux                                                                                                                                                                          |
  | Difficulty       | Medium                                                                                                                                                                         |
  | Vector           | <span className="vbadge vbadge-web">Web</span>                                                                                                                                 |
  | IP               | `10.10.11.134`                                                                                                                                                                 |
  | Retirement date  | 2022-03-10                                                                                                                                                                     |
  | Skills           | Git Source Leak Exploit (GitHack) AWS Enumeration Lambda Function Enumeration Authentication Bypass Abusing JWT Server Side Template Injection (SSTI) Tar Symlink Exploitation |
</div>

## Writeups

| Language | Author      | Format | Link                                                                      |
| -------- | ----------- | ------ | ------------------------------------------------------------------------- |
| 🇪🇸 ES  | **S4vitar** | Vídeo  | [Open](https://www.youtube.com/watch?v=tMsK6ZiB7CQ)                       |
| 🇬🇧 EN  | **0xdf**    | Texto  | [Open](https://0xdf.gitlab.io/2022/03/10/htb-epsilon.html)                |
| 🇬🇧 EN  | **IppSec**  | Vídeo  | [Open](https://www.youtube.com/@ippsec/search?query=HackTheBox%20Epsilon) |

## Skill resources

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

| Skill                                 | Source      | Link                                                                          |
| ------------------------------------- | ----------- | ----------------------------------------------------------------------------- |
| SSTI (Server-Side Template Injection) | PortSwigger | [Open](https://portswigger.net/web-security/server-side-template-injection)   |
| Authentication Vulnerabilities        | PortSwigger | [Open](https://portswigger.net/web-security/authentication)                   |
| Remote Code Execution (RCE)           | HackTricks  | [Open](https://book.hacktricks.wiki/en/pentesting-web/command-injection.html) |
| JSON Web Tokens (JWT)                 | PortSwigger | [Open](https://portswigger.net/web-security/jwt)                              |

## Related skills worth mastering

Local File Inclusion (LFI) · Remote File Inclusion (RFI) · Shellshock (CVE-2014-6271)

## If you liked this machine, try

* [Noter](/en/htb/machines/linux/medio/noter) — Linux, Medium
* [Helpline](/en/htb/machines/windows/dificil/helpline) — Windows, Hard
* [Backend](/en/htb/machines/linux/medio/backend) — Linux, Medium
* [BackendTwo](/en/htb/machines/linux/medio/backendtwo) — Linux, Medium
* [Flustered](/en/htb/machines/linux/medio/flustered) — Linux, Medium

***

## 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:epsilon" data-giscus-lang="en" />

*Last updated: 2026-06-07*

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