DivideAndScan : Divide Full Port Scan Results And Use It For Targeted Nmap Runs

DivideAndScan is used to efficiently automate port scanning routine by splitting it into 3 phases:

1. Discover open ports for a bunch of targets.
2. Run Nmap individually for each target with version grabbing and NSE actions.
3. Merge the results into a single Nmap report (different formats available).

For the 1st phase a fast port scanner is intended to be used (Masscan / RustScan / Naabu), whose output is parsed and stored in a single file database (TinyDB). Next, during the 2nd phase individual Nmap scans are launched for each target with its set of open ports (multiprocessing is supported) according to the database data. Finally, in the 3rd phase separate Nmap outputs are merged into a single report in different formats (XML / HTML / simple text / grepable) with nMap_Merger.

Potential use cases:

• Pentest engagements / red teaming with a large scope to enumerate.
• Cybersecurity wargames / training CTF labs.
• OSCP certification exam.

How It Works

How To Install

Prerequisites

To successfully divide and scan we need to get some good port scanning tools.

Note: if you don’t feel like messing with dependecies on your host OS, skip to the Docker part.

Nmap

sudo apt install nmap sudo xsltproc -y
sudo nmap –script-updatedb

Masscan

cd /tmp
git clone https://github.com/robertdavidgraham/masscan.git
cd masscan
make
sudo make install
cd && rm -rf /tmp/masscan

RustScan

cd /tmp
wget -qO- https://api.github.com/repos/RustScan/RustScan/releases/latest \
| grep “browser_download_url.*amd64.deb” \
| cut -d: -f2,3 \
| tr -d \” \
| wget -qO rustscan.deb -i-
sudo dpkg -i rustscan.deb
cd && rm /tmp/rustscan.deb
sudo wget https://gist.github.com/snovvcrash/c7f8223cc27154555496a9cbb4650681/raw/a76a2c658370d8b823a8a38a860e4d88051b417e/rustscan-ports-top1000.toml -O /root/.rustscan.toml

Naabu

sudo mkdir /opt/projectdiscovery
cd /opt/projectdiscovery
wget -qO- https://api.github.com/repos/projectdiscovery/naabu/releases/latest \
| grep “browser_download_url.*linux-amd64.tar.gz” \
| cut -d: -f2,3 \
| tr -d \” \
| sudo wget -qO naabu.tar.gz -i-
sudo tar -xvzf naabu.tar.gz
sudo mv naabu-linux-amd64 naabu
sudo rm naabu.tar.gz README.md LICENSE.md
sudo ln -vs /opt/projectdiscovery/naabu /usr/local/bin/naabu

Installation

DivideAndScan is available on PyPI as divideandscan, though I recommend installing it from GitHub with pipx in order to always have the bleeding-edge version:

~$ pipx install -f “git+https://github.com/snovvcrash/DivideAndScan.git”
~$ das

For debbugging purposes you can set up a dev environment with poetry:

~$ git clone https://github.com/snovvcrash/DivideAndScan
~$ cd DivideAndScan
~$ poetry install
~$ poetry run das

Note: DivideAndScan uses sudo to run all the port scanners, so it will ask for the password when scanning commands are invoked.

Using From Docker

You can run DivideAndScan in a Docker container as follows:

~$ docker run -it –rm –name das -v pwd:/app snovvcrash/divideandscan

Since the tool requires some input data and produces some output data, you should specify your current working directory as the mount point at /app within the container. You may want to set an alias to make the base command shorter:

~$ alias das=’docker run -it –rm –name das -v pwd:/app snovvcrash/divideandscan’
~$ das

How To Use

Preparations

Make a new directory to start DivideAndScan from. The tool will create subdirectories in CWD to store the output, so I recommend launching it from a clean directory to stay organized:

~$ mkdir divideandscan
~$ cd divideandscan

 Filling The DB

Provide the add module a command for a fast port scanner to discover open ports in a desired range.

#Masscan
~$ das add masscan ‘–rate 1000 -iL hosts.txt -p1-65535 –open’
#RustScan
~$ das add rustscan ‘-b 1000 -t 2000 -u 5000 -a hosts.txt -r 1-65535 -g –no-config’
#Naabu
~$ das add naabu ‘-rate 1000 -iL hosts.txt -p – -silent -s s’
#Nmap, -v flag is always required for correct parsing!
~$ das add nmap ‘-v -n -Pn –min-rate 1000 -T4 -iL hosts.txt -p1-65535 –open’

When the module completes its work, a hidden directory .db is created in CWD containig the database file and raw scan results.

Targeted Scanning

Launch targeted Nmap scans with the scan module. You can adjust the scan surface with either -hosts or -ports option:

#Scan by hosts
~$ das scan -hosts all -oA report1
~$ das scan -hosts 192.168.1.0/24,10.10.13.37 -oA report1
~$ das scan -hosts hosts.txt -oA report1
#Scan by ports
~$ das scan -ports all -oA report2
~$ das scan -ports 22,80,443,445 -oA report2
~$ das scan -ports ports.txt -oA report2

To start Nmap simultaneously in multiple processes, specify the -parallel switch and set number of workers with the -proc option (if no value is provided, it will default to the number of processors on the machine):

~$ das scan -hosts all -oA report -parallel [-proc 4]

The output format is selected with -oX, -oN, -oG and -oA options for XML+HTML formats, simple text format, grepable format and all formats respectively. When the module completes its work, a hidden directory .nmap is created in CWD containig Nmap raw scan reports.

Also, you can inspect the contents of the database with -show option before actually launching the scans:

~$ das scan -hosts all -show

Merging The Reports

In order to generate a report independently of the scan module, you should use the report module. It will search for Nmap raw scan reports in the .nmap directory and process and merge them based on either -hosts or -ports option:

#Merge outputs by hosts
~$ das report -hosts all -oA report1
~$ das report -hosts 192.168.1.0/24,10.10.13.37 -oA report1
~$ das report -hosts hosts.txt -oA report1
#Merge outputs by ports
~$ das report -ports all -oA report2
~$ das report -ports 22,80,443,445 -oA report2
~$ das report -ports ports.txt -oA report2

Note: keep in mind that the report module does not search the DB when processing the -hosts or -ports options, but looks for Nmap raw reports directly in .nmap directory instead; it means that -hosts 127.0.0.1 argument value will be successfully resolved only if .nmap/127-0-0-1.* file exists, and -ports 80 argument value will be successfully resolved only if .nmap/port80.* file exists.