What is Pentesting and what are Pentesting tools?
The goal of pentesting (penetration testing) is to detect security vulnerabilities by utilizing specific processes, tools and services. You can either opt-in for a manual pentest, conducted by a team of white-hat hackers, or you can use an automated approach, having a software solution perform the test. Either way, the target of a pentest can be a computer system, a network or a web application.
When conducting a pentest, the pen testers use a range of tools, most often the same tools a malicious attacker would use. Those tools can include port scanners, vulnerability scanners, network sniffers, web proxies and password crackers.
If you want to learn more about this topic, we have a great article about penetration testing.
Open Source pentesting Tools on the list:
1. OWASP ZAP
2. Zenmap
3. Scapy
4. BeEF
5. Firefox Addons
6. Sqlmap
7. Kali NetHunter
Alternatives
1. OWASP ZAP

OWASP ZAP (Zed Attack Proxy) is a web app vulnerability scanner maintained by an international team of volunteers, and is one of the most active OWASP projects. You can configure OWASP ZAP to detect vulnerabilities automatically, or you can trigger the scans manually. You can also choose if you want to use it as a man-in-the-middle, between your browser and the application’s server, or as a standalone application. If you are not a fan of GUI, you can use OWASP ZAP as a daemon process, without UI.
Platform support: Windows, Linux, Mac OS/X, Docker
License: Apache License 2.0
2. Zenmap

Zenmap, the official GUI for the Nmap Security Scanner, is a free and open source tool that aims to make Nmap easy to use for beginners, while providing advanced features for experienced Nmap users. The tool is multi-platform and will work on Windows, MacOS, Linux, BSD, etc. Profiles can be created for frequently used scans to make them easier to run again and again. A command creator allows you to create Nmap command lines interactively. The results of a scan can be saved and retrieved at a later time. Scan results saved in the past can be compared to see how they differ. Recent scan results are saved in a database that can be searched.
Platform Support: Multi-platform (Windows, MacOS, Linux, BSD, etc.
License: Nmap Public Source License
Scapy

Scapy is capable of forging or decoding packets of a wide variety of protocols. This open source pentesting tool will allow you to transmit, capture, and match requests and responses, among other things. You can use Scapy to perform most tasks, such as scanning, tracerouting, probing, unit tests, attacks, and network discovery, but you can also send invalid frames, inject your own 802.11 frames, and combine techniques.
Platform Support: Linux, Windows, MacOS/X and most UNIXes with libpcap
License: GPLv2
BeEF

BeEF is an open source, GUI-based pentesting tool. The BeEF bypasses hardened network perimeters to examine how hackers could exploit security weaknesses in the web browser itself. One or more web browsers can be hooked by BeEF to serve as launching pads for further attacks. It can run on many platforms, including Ubuntu, MacOS, Windows, and others, but it requires Ruby and SQLite to run.
Platform Support: Mac OSX 10.5.0 or higher / modern Linux
License: MIT License
Firefox Addons

Firefox is the go-to web browser for most system administrators when it comes to pentesting activities. The browser is open source and comes with the ability to easily install addons to it. Mozilla has already compiled a list of 30 addons you can choose from, so you don’t have to spend time searching. You’ll find Hackbar, an addon that helps you test for SQL Injection and XSS attacks in the address bar, ViewStatePeeker to examine the ASP.Net viewstate, and Firebug to track down fraudulent JavaScript code on servers.
Platform Support: Firefox Browser
License: Check for every specific addon.
Sqlmap

To take over the control of the database server, attackers usually use SQL injections. To be a step ahead, use sqlmap to detect possible weak spots the attackers could take advantage of. Sqlmap is a free and open source pentesting tool for SQLi in Windows and UNIX/Linux systems. Sqlmap comes with the ability to test for different SQLi techniques, including boolean-based blind, time-based blind, stacked queries, out-of-band and others. If you are not familiar with those techniques and would like to know more, we have a great article for you covering SQL Injection in depth. SQLMap supports a wide range of DBMSs in addition to MS SQL Server, MS Access, Oracle, IBM DB2, Firebird, SAP MaxDB, and HSQLDB. You can also embed sqlmap technology in proprietary software, but this requires an alternate license.
Platform Support: Cross Platform
License: GNU General Public License v2.0
Kali NetHunter

In our fast-paced world, a system administrator may have to perform pentests on-the-go. Kali NetHunter is the first open-source Android penetration testing platform. Thanks to Kali NetHunter, you will be able to access the Kali toolset from various supported Android devices. NetHunter supports various features unique to the Android platform. NetHunter comes with an interface that will allow you to easily work with complex configuration files through a local web interface. Kali NetHunter is an excellent network security tool thanks to this feature, along with a custom kernel that supports 802.11 wireless injection and a preconfigured connect back VPN service.
Platform Support: Android
License: GNU GPL
Alternatives to open source tools
People often opt-in for open source tools because they are free, however you don’t have to limit yourself to open source tools if you want to avoid paying for proprietary tools. Some, like Bright, have a bounteous free plan. In the best case, you won’t even be limited in the features you can use, so try to find free solutions that are not necessarily open source. Proprietary tools have a big advantage on their side – the support you get with them.
Sign-up for Bright’s free developer security testing automation account and enhance your pen tests with the only no false positive API and application security scanner – sign-up now.
