Penetration testing is crucial to ensuring a resilient security posture within an organization. It simulates an attack on the system, application, or network to discover vulnerabilities before hackers do.

Developers often use penetration testing to verify that applications’ internal resources are safe from unauthorized access. In this situation, the tester or ethical hacker serves as a malicious actor. They gather as much information about the system as possible to find exploitable weaknesses. Based on the findings, developers implement solutions and even use further penetration testing to ensure these solutions work.

This example is only one of many. Developers must ensure all applications’ critical components — operating systems (OS), device drivers, networks, databases, frameworks, packages, code, and libraries — are safe. Manually performing frequent penetration testing is costly and time-consuming, so many organizations use automated tools to test more quickly and efficiently.

Many penetration testing tools are available, and selecting the right one (or more) can seem daunting. In this article, we’ll explore eight popular penetration testing tools, their benefits, and their ideal use cases.

The best penetration testing tool for you

Various penetration testing tools focus on different techniques and use cases. This list’s goal isn’t to determine an overall “best” choice, but to help you find the right tool for your project’s unique needs.

1. Metasploit framework

Metasploit is an open source framework that scans networks and servers to expose exploitable weaknesses. This highly-customizable tool contains a vast library of over 1,600 exploits and nearly 500 payloads.

Its community-driven development also offers automated exploitation and post-exploitation tools. These tools allow developers to perform both offensive and defensive security tasks. Metasploit features the Vulnerability Validation Wizard to list security issues in order of severity, enabling developers to prioritize which vulnerabilities to mitigate first.

The Metasploit framework is suitable for organizations of any size, and its free, easy-to-use architecture helps protect applications from various weaknesses.

2. Nmap

Port scanning is a common tactic among cybercriminals to discover a system’s vulnerabilities. The bad actors find open ports and other potentially useful information — such as the application’s hosts and OS — to create their plan of attack. As a result, port scanners play an integral role in many organizations’ penetration testing.

Network Mapper (Nmap) scans and identifies a network’s hosts and services. This popular open source tool helps developers identify and audit any open ports on their system that malicious actors can exploit. Nmap’s other helpful features include host discovery and OS detection.

Nmap supports multiple scanning types and techniques, so it’s a versatile tool for numerous use cases. The scanner’s many tutorials and whitepapers will help users get started, and their large community works together to offer solutions.

3. sqlmap

sqlmap is an open source penetration testing tool to detect SQL injection vulnerabilities within web applications automatically. Hackers use these vulnerabilities to exploit applications.

With sqlmap, testers can perform various SQL injection attacks — such as time-based, blind, error-based, and boolean-based — to extract sensitive information from a database. sqlmap supports many databases, including MySQL, PostgreSQL, and Oracle. Its other features include cracking hashes, dumping tables and columns, and fingerprinting. And because sqlmap executes penetration testing automatically, users simply need to start it, specify a few parameters, and it does the rest.

Unlike more general-use tools like Metasploit, sqlmap offers a specialized approach to penetration testing. It also doesn’t require prior experience with scripting languages — a basic familiarity with database queries suffices.

4. Burp Suite

Burp Suite incorporates comprehensive Java-based tools for web application security testing. The testing tool includes a proxy server that enables testers to intercept and modify HTTP and HTTPS traffic between the browser and server. Burp Suite also scans for vulnerabilities like cross-site request forgery (CSRF), structured query language (SQL) injection, and cross-site scripting (XSS). Also, Burp Suite’s tools help manipulate requests and responses, analyze application behavior, and automate tasks.

Burp Suite’s free community edition offers basic features, including a scanner, proxy server, and intruder tools. The professional and enterprise editions require an annual subscription and contain more powerful advanced features. However, all three packages are easy to use and support manual and automated dynamic testing. 

5. OWASP ZAP

Like Burp Suite, OWASP Zed Attack Proxy (ZAP) is a Java-based web application scanner. ZAP’s automated scanners help users detect vulnerabilities like SQL injections and XSS.

OWASP ZAP also offers advanced features for scripting attacks, intercepting and modifying traffic, and generating reports. These features allow for comprehensive and customizable penetration testing.

This free tool has an active community to help when users get stuck. It’s excellent for developers working on applications requiring user inputs and a database connection.  

6. Nikto

Nikto is a free web server scanner that identifies potential security issues in web servers and applications. Like OWASP ZAP, it’s an open source alternative to Burp Suite.

Written in Perl and accessed via the command line, Nikto identifies outdated software versions, insecure connections, and other known vulnerabilities. Users can also customize its scan functions, such as specifying which plugins to run and excluding specific files or directories.

On top of standard vulnerability scanning, Nikto is an excellent tool for ensuring servers and files are secure and up-to-date.

7. w3af

w3af is a web application attack and audit framework that allows testers to identify and exploit vulnerabilities. Compatible with Windows, Linux, OS X, OpenBSD, and FreeBSD, this tool identifies more than 200 web application vulnerabilities.

The w3af framework includes automatic scanners to detect XSS, SQL injection, PHP misconfigurations, guessable credentials, and unhandled application errors, among other vulnerabilities. The framework’s advanced features can also script attacks, intercept and modify traffic, and generate reports.

The well-documented w3af framework has graphical and console interfaces where users can initiate scans with just a few clicks.

8. Snyk Open Source

Snyk Open Source scans and identifies security vulnerabilities in an application’s open source libraries and frameworks. It’s compatible with an API, Snyk CLI, or Snyk Web UI. 

Unlike the other seven tools, users can integrate Snyk Open Source during development to catch vulnerabilities early. Its remediation advice and continuous monitoring features provide alerts when it discovers new vulnerabilities.

The well-documented Snyk Open Source offers several deployment options. Its usability and scan depth give it an edge over other penetration testing tools. However, Snyk Open Source works best alongside other penetration tools, like network scanners, to provide total security coverage.

Choosing your penetration testing tool

Penetration testing affirms confidence in the application’s security posture. Organizations can protect systems from future exploitation by detecting and correcting vulnerabilities in networks, APIs, and code as soon as possible.

This list covers only a few automated testing tools. As no single application can detect all potential vulnerabilities, most developers combine tools to find all their attack vectors. The best approach is to explore and experiment with various options to find the best tools for your specific needs.