What Is Web Application Penetration Testing?
Web application penetration testing is a simulated attack on your organization to reveal any of the top OWASP application flaws it may have. Unlike other types of penetration testing, web app testing restricts the testing scope to application entry points, API endpoints, and other components regarding web applications and APIs.
Why You Need to Test Web Applications
Performing web application penetration testing allows you to discover vulnerabilities before they become breaches in production. As with all forms of penetration testing, it helps you stay one step ahead of potential cyber criminals.
More generally, web app pen testing helps you maintain the integrity, availability, and confidentiality of your application and its data.
How Does Web Application Penetration Testing Work?
Web app penetration testing follows a standard procedure:
Reconnaissance
The process begins at the reconnaissance stage, in which a tester crawls and fingerprints your application. S(he) utilizes a suite of tools, such as Burp Professional, OWASP ZAP, and Web Inspect, to do so. The goal here is to find APIs, associated applications, entry points, user roles, and third-party hosted content, among other valuable information.
During reconnaissance, the tester also analyzes API endpoints, uncovering their syntax and functionality.
Attack
Now that the tester has ample information about your application, s(he) begins the simulated attack. Once again, a host of different tools are involved. During this attack phase, a tester may use fuzzers, web app scanners, and proxy servers to manipulate traffic and illicit unexpected behavior from the application.
Web Application-Specific Vulnerabilities
As we mentioned earlier, web app pen testing looks explicitly for the OWASP Top 10 Application Security Risks and OWASP Top 10 API Risks. We’ve outlined them for you below:

Even though some of the vulnerabilities appear on both lists, like Broken Authentication, it’s imperative to test for them separately on their distinct components (App-level vs. API-level).

Report
Reporting is the most valuable step in any penetration testing process. During the attack simulations, the tester records the actions (s)he took and what vulnerabilities popped up. Additionally, (s)he explains the findings, sets risk ratings, and gives recommendations on how to remediate.
Is Web Application Penetration Testing Right for You?
After learning a bit more about the process, you should now have a better idea of whether web app penetration testing is right for your organization. If your organization uses a web app, implements APIs, or integrates with outside software, it should at least be on your radar.
All it takes is one vulnerability to bring disaster. Protect yourself and get a web app penetration test today.