Recon-NG: What is It and How to Use It as an Ethical Hacker?

Searching for information about a target might sound like detective work… and honestly, it’s not far off. Before starting an audit or a penetration test, ethical hackers have to switch into investigator mode and dig through heaps of public data. Who’s behind that domain? What subdomains does it have? Are there any exposed emails floating around unintentionally? The good news is, you don’t have to do all of this manually—there are tools that save you a ton of work. One of the most powerful is Recon-ng.

This isn’t just another script. Recon-ng is like a digital intelligence lab where you can automate tons of reconnaissance tasks without breaking a sweat.

What Is Recon-ng?

Recon-ng is an open-source intelligence gathering platform, developed in Python, that mimics the Metasploit environment but is focused exclusively on information collection (OSINT - Open Source Intelligence).

This tool offers a framework with a wide range of modules that automate common reconnaissance tasks, such as searching for domains, collecting email addresses, retrieving geolocation data, and much more. All of this can be done quickly and efficiently from a very intuitive interactive terminal.

Advantages of Recon-ng

Recon-ng stands out for several reasons:

1. Automation: It allows you to automate processes that would typically require multiple tools and scripts.

2. Intuitive CLI Interface: It features a command-line environment very similar to Metasploit, which is easy to learn and use.

3. Modularity: It includes dozens of modules covering various types of data collection.

4. API Integration: Many modules can be linked to external services like Shodan, Bing, GitHub, among others.

5. Exportable Results: It allows you to generate reports in various formats (JSON, CSV, HTML)

General Structure of Recon-ng

Before diving into how to use it, it’s important to understand its structure:

1. Workspaces: These are separate environments for storing data by target.

2. Modules: Scripts focused on specific tasks, organized by categories (recon, exploitation, reporting, etc.).

3. API Keys: Some information sources require authentication via API.

4. Database: Recon-ng maintains an integrated database to store all the collected information

Read more: FinalRecon Tool: Automatic Web Scanning for Pentesters

How to Install Recon-NG

Recon-ng is available for Linux and macOS systems. You can easily install it from GitHub using the following commands:

git clone https://github.com/lanmaster53/recon-ng.git
cd recon-ng
pip install -r REQUIREMENTS
python3 recon-ng

You can also run it directly from Kali Linux, where it comes pre-installed on many distributions.

Getting Started: First Steps with Recon-ng

1. Launch Recon-ng

To get started, simply type: python3 recon-ng. This will open the interactive console prompt of Recon-ng.

2. Create a Workspace

Using a workspace allows you to keep information separated by target: workspaces create company_target

3. Add Initial Information

You can enter domains, IPs, or names directly: add domains company.com

4. View Available Modules

Use the command: show modules. This will display a list of available modules, categorized by their function.

Types of Modules in Recon-ng

Recon-ng offers a wide variety of modules. Here they are grouped by purpose:

a. Reconnaissance Modules (recon)

1. recon/domains-hosts/bing_domain_web: Searches for subdomains using Bing.

2. recon/domains-contacts/whois_pocs: Extracts contact information from WHOIS records.

3. recon/hosts-hosts/resolve: Converts hostnames to IP addresses.

b. Exploitation Modules (exploitation)

Although Recon-ng is not primarily an exploitation tool, it does include modules that simulate exploitation actions, such as bulk email sending or brute force testing on web forms.

c. Reporting Modules (reporting)

1. reporting/csv: Exports data in CSV format.

2. reporting/html: Generates an HTML report ready for presentation.

Recon-ng in the Red Team? Absolutely

When it comes to ethical hacking, it's common to encounter two major teams: the Red Team and the Blue Team. While the Blue Team is responsible for defending, monitoring, and strengthening system security, the Red Team specializes in thinking like the enemy and identifying weaknesses before a real attacker does.

This is where Recon-ng truly shines. For a Red Team, every second counts, and having a comprehensive view of the target company's environment from the very beginning is key to designing realistic and effective attacks. Recon-ng enables automated data collection and helps build a solid foundation on which to craft attack scenarios.

Ways Recon-ng Supports a Red Team:

1. Attack Surface Mapping: By discovering subdomains, IPs, and exposed paths, it helps identify potential entry vectors.

2. Sensitive Metadata Collection: With modules that explore public documents, it’s possible to uncover internal information that can be used for social engineering or spear phishing attacks.

3. Simulated Campaign Preparation: Knowing which emails are active and publicly available aids in setting up controlled phishing tests.

4. Validation Reporting: The generated HTML or CSV reports document the entire process and can be transparently presented to the client.

Comparison: Recon-ng vs Other OSINT Tools