How to Do Penetration Testing for Web Application?

Web Application Penetration Testing - Guide

The popularity of web apps has created an alternative vector for hackers to attack. Web applications usually contain sensitive private information and must remain completely secure. Web application penetration testing is designed to identify web app vulnerabilities in time, which can then be fixed. Thus, no hackers will be able to gain access to users’ sensitive data. They will not be able to hack into the system and expose the company and users to financial losses.

What is web penetration testing?

It includes a series of steps to collect all the necessary information about an object, identify weaknesses and vulnerabilities, and investigate exploits used to penetrate the system by hackers. A penetration test consists of four main components: research and use, information gathering, reporting and recommendations, and forwarding with ongoing support.

Web application pen testing can be done either manually or automatically and is typically targeted at endpoints:

  1. network endpoints;
  2. wireless networks;
  3. servers;
  4. mobile and wireless devices;
  5. network security devices;
  6. other areas of influence, such as software applications.

Web penetration testing is a collection of techniques in which testers simulate different cyberattacks to identify potential threats to a web application, service, or website. It should be noted that at the moment, Web servers in the cloud are extremely vulnerable to attacks from third parties.

Types of Vulnerabilities Identified by Web App Penetration Testing

Web application penetration testing examines all the weaknesses in a company’s IT infrastructure, trying to detect and exploit them securely.

These vulnerabilities are:

  • Unintended flaws in the design of the program code;
  • Backdoors in the operating system;
  • Incorrect implementation of software configuration management;
  • Misuse of the actual software application.

Types of Web Penetration Testing

Specialists test Web applications in two ways. First, tests can be designed to simulate an external or internal attack.

  1. Internal Penetration Testing

The internal pen testing allows you to determine if web application vulnerabilities exist inside the corporate firewall. It runs within the organization on the local network and includes testing on the intranet. Internal testing is often ignored, but it is extremely important. After all, attacks are also possible from disgruntled contractors, fired and offended employees who are well aware of the company’s security system features, and so on.

  1. External Penetration Testing

There is a high probability of hacker attacks committed from outside the organization. Therefore such testing is necessary. In this case, testers behave like hackers who know little about the internal system and thus look for vulnerabilities. Testers are given only the IP address of the target system and no other information.

3 Phases of Web Application Penetration Testing Process

Let’s talk about the three most important phases of testing that specialists carry out.

  1. Planning phase

Before starting testing, you should carefully plan everything, analyze how testing will be carried out, what types of testing will be performed, and so on. At this stage, the area of ​​our testing is determined. Here, the availability of documentation for testers is extremely important, for example, documents with a detailed description of integration points, web architecture, etc.

In addition, the tester must understand the basics of the HTTP / HTTPS protocol and web application architecture. Criteria for success must also be approved. It is desirable to familiarize yourself with the results of the previous testing if it was previously carried out. Finally, testers should have a detailed understanding of firewalls and other protocols.

  1. Attacks/Execution Phase

Typically, Web penetration testing can be performed from anywhere. However, for successful testing, specialists must ensure that tests are run with users with different roles. It should be done because the system may behave differently towards users with different privileges.

Testers should carefully follow the success criteria. In this stage, the tester determines what needs to be done after discovering that the system has been compromised. After that, reports are created on the vulnerabilities found, the testing process, methodology, and the like.

  1. Post Execution Phase

After all interested parties receive reports on the testing, work on the identified errors, fixes for detected mistakes, and ways to eliminate vulnerabilities should be proposed. After fixing, the vulnerabilities are retested. Then the cleanup takes place. The experts make changes to the proxy server settings, so a cleanup needs to be done. 


The web app pen test aims to analyze the security of web applications in the company. This test is performed to audit the safety of the software development lifecycle. It is very important to find web application security vulnerabilities in time to prevent hackers from breaking into the system and causing harm to users and the company. Otherwise, the simplest defects in software development and the wrong web server can lead to big losses for customers.


What’s the first step of a penetration test for a web application?

Before starting testing, you should carefully analyze and plan everything and determine the testing area. Care should be taken to ensure that specialists have all the necessary documentation, for example, documents detailing integration points. In addition, you should familiarize yourself with the results of the previous testing. Then it is possible to proceed to the remaining steps.

What are the basic testing tools of web application penetration testing?

Among the tools, it is possible to distinguish the following:
– Astra Pentest
– Nessus
– SQLmap
– Nikto
– Intruder
– W3AF
– Metasploit
– WireShark and so on.

What are the five stages of pen testing?

There are five penetration testing phases: reconnaissance, scanning, vulnerability assessment, exploitation, and reporting.