Companies are continuously seeking innovative ways to protect their web apps due to a variety of cyber threats in today’s digital environment. Penetration testing is one of those approaches that has already become an important element of any good security plan.

Penetration testing is continually increasing in popularity, which also known as pen tests or pen is testing. The market for pen testing is projected to rise from $1.7bn in 2020 to $4.5bn in 2025, according to Research and Markets.

A pen test is a test focused only on a web application, not on a whole network or enterprise, as the name indicates. In order to obtain sensitive data, penetration tests for online applications are performed through simulated assaults within and outside.

A pen test allows us to find any security issues in both the overall web application and its particular components (source code, database, and back-end network).This aids the developer in prioritizing the identified web app vulnerabilities and threats and devising mitigation measures.

Why is penetration testing important?

Almost everything we do these days is accessed through the internet. The majority of transactions, from shopping to banking to everyday activities, may be completed digitally. There are varieties of web programs that may be utilized to do these tasks online.

The rise in popularity of web applications has also opened up new attack patterns that malevolent third parties might use for their particular advantage. Because online applications frequently store or communicate sensitive data, it is critical to keep them secure at all times, especially those that are publicly accessible via the Internet.

In summary, online penetration, testing is a preventive management tool that allows you to assess the entire health of a system’s security layer.

These are the common objectives of web app testing:

  • Unknown vulnerabilities should be identified
  • Monitor the efficiency of current security policies
  • Firewalls, routers, and DNS are examples of publicly exposed components that should be tested.
  • Determine the most sensitive attack route
  • Find lapse that might lead to theft of data

If you look at the present usage of the Internet, you will see that mobile Internet has increased dramatically, which indicates that the possibility for mobile attacks is growing directly. By using mobile devices, consumers are more likely to assault websites or apps. Pen testing thus plays a key role in the creation of software and helps to construct a safe system that consumers may use without worrying about hacking or data theft

Web applications penetration test types

Pen testing for web applications can be accomplished in one of two ways: by simulating an internal or external attack. Let us have a look at how these various forms of attacks are planned and executed:

Internal pen testing method

Internal penetration testing, as the title indicates, is done within the enterprise through LAN, and includes testing web applications hosted on the intranet.

This makes it easier to find any potential weaknesses within the corporate firewall. One of the most common misunderstandings is that assaults can only happen from the outside, therefore developers frequently disregard or undervalue internal Pen testing.

Some internally originating attacks include:

  • Attacks by aggressive workers, contractors or other parties who have renounced the internal security policies and passwords, but have not yet access to them
  • Attacks on Social Engineering
  • Phishing Attacks Simulation
  • User Privileges Attacks

The pen test is done by trying to access the environment to determine the likely route of assaults, without proper credentials.

External pen testing method

In contrast to an internal pen test, external pen tests focus on web applications hosted from outside the company.

Testers, often known as ethical hackers, lack information about the internal system and the organization’s security layers. The IP address of the target system is just provided to simulate external attacks. No further information can be provided and the testers must browse public web pages to find, penetrate or breach further information about the target host. The external pen test covers firewalls, servers and IDS testing of the enterprise.

How is Web App Penetration Testing Performed?

Instead of the application itself, pen testing for Web apps focuses on the environment and the setup procedure. This includes collecting information about the web app, mapping the network in which the application is hosted and researching any points of injection or manipulation.

The steps in web application penetration testing are here:

Step 1: Active and Passive recognition

The first step is the recognition or information collection phase in the web app pen testing. This stage offers the tester information to find and exploit web application vulnerabilities.

Passive recognition is collecting information that is easily available through the internet and does not involve the target system directly. This usually happens with Google, starting with subdomains, links, earlier versions, etc.

Active recognition means, however, that the target system is tested directly to receive a result. Here are some examples of active recognition methodologies:

Fingerprinting with Nmap: The Nmap network scanner can be used to obtain information about the web app’s scripting language, the server’s operating system, server software and versions, open ports, and presently running services.

Shodan Network scanner: This tool helps you obtain extra publicly available information about the web app, such as geolocation, server software utilized, accessible open ports, and more.

DNS Lookups (Forward and Reverse): This approach enables you to link newly identified subdomains to their corresponding IP addresses. Burp Suite can also be used to automate this process.

DNS Zone Migration: To find out which DNS servers are being utilized, use the lookup command. Another alternative is to use DNS server identification websites before attempting the DNS zone migration with the dig command.

Determine Related Other Sites: Because of the traffic that goes between the external websites and the target website, this aspect of the information gathering phase is critical. Using the Burp Suite takes care of this step for you.

Evaluate HEAD and OPTION Responses: Examine the replies to HEAD and OPTIONS requests. HTTP queries reveal the web server’s software and version, as well as other useful information. When visiting the target website, you can utilize Burp Suite’s intercept functionality to acquire this information.

Data Collected from Error Pages: Error pages include a lot more information than you may think. You may find out what server and version your target website is running on by changing the URL and creating a 404 Not Found error on it.

Examining the Source Code: Examining the source code can help you discover helpful information that can be used to identify vulnerabilities. It assists you in determining the app’s operating environment as well as other pertinent information.

Detailing All Data: Once you have gathered all of this data, you will want to arrange and document your results so you can use them as a baseline for future research or to uncover vulnerabilities to exploit.

Step 2: Attacks or the Phase of Execution

The real exploitation is the following stage. You carry out the attacks in this phase using the information obtained during the reconnaissance step.

You can employ a variety of methods to carry out the attacks, and here is where data gathering comes in handy. Based on your previous research, the information you gathered will assist you in narrowing down the tools you require.

Let us have a look at the most popular web application penetration tools in use today:

1: Nmap

Nmap, or Network Mapper, is more than just a research and scanning tool. It’s utilized for network discovery as well as security auditing. It has a scripting module that may be used for vulnerability and malware detection, as well as the execution of exploitations, in addition to providing basic information on the target website.

2: Wireshark

Wireshark is one of the most widely used network protocol analyzers today, allowing for in-depth protocol inspection as well as live traffic capture and offline analysis of a captured file. For documentation and further analysis, the data can be exported in XML, PostScript, CSV, or plain text format.

3: Metasploit

This pen-testing tool is more of a framework than a separate program. This can be used to construct specialized tools activities. Metasploit can be used to:

  • Choose and configure the exploit that will be used.
  • Choose and configure the payload that will be used.
  • Choose an encoding scheme and set it up.
  • Carry out the exploit

4: Nessus

This vulnerability scanner aids testers in detecting web application vulnerabilities, configuration issues, and even the existence of malware. This tool, on the other hand, is not meant to be used to carry out exploitations, but it can be quite useful for reconnaissance.

5: Burp Suite

Burp Suite has already been mentioned a few times, and for good reason: it is an all-in-one platform for evaluating the security of online applications. It includes tools such as an intercepting proxy, an application-aware spider, an advanced web application scanner, an intruder tool, a repeater tool, and a sequencer tool that can be used at any stage of the testing process.

Step 3: Recommendations and Reporting

The next step is to write the web application pen testing report after the data collection and exploitation steps are completed. Make sure your report has a clear structure and that all of your findings are backed up with facts. Keep it simple by describing the process in detail and sticking to the methods that worked.

Besides writing successful exploits, you should also categorize them according to their criticality level, so that engineers can focus on the more important attacks first.