# 20000 - Usermin

**Usermin** is a web-based interface that lets regular users manage their Unix/Linux accounts through a browser. It allows tasks like reading email, managing files, and editing cron jobs, typically running on port `20000` as part of the **Webmin suite**.

```bash
# Identify a UserMin port via nmap
20000/tcp open  http    MiniServ 1.820 (Webmin httpd)
```

## Versions

### ≤ 1.820

There is an **authenticated remote code execution (RCE)** vulnerability in Usermin `≤ 1.820` by abusing the GnuPG functionality to execute arbitrary commands on the target system. An available [PoC](https://github.com/CSpanias/usermin-rce.py) exists.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://x7331.gitbook.io/boxes/services/tcp/usermin-20000.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.