Every business owes a part of its successful outreach to customers via its web applications. Today’s web applications are practically the front-face of businesses for achieving several goals. However, they are equally vulnerable to various kinds of cyberattacks, be it brute force, SEO Spam, unauthorized access to important databases, etc. Web application security testing is the exact solution to this problem as it runs through the entire system to assess its strength against such issues.
What are the goals of web application penetration testing?
The purpose of such a procedure involves testing for vulnerabilities, test applications for their responses to simulated attacks, etc. It will also test applications developed in-house by your own developers or a third-party vendor. Web application penetration testing is an important part of any business’s security strategy and should be conducted periodically and comprehensively.
A good penetration testing procedure tests for vulnerabilities that are both commonly found and those found during the vulnerability assessment. For the first category, a good reference is the Open Web Application Security Project (OWASP) Top 10 list of vulnerabilities with the ten most critical security issues in applications. Some of the issues that you can test your web application for include:
- Weak session management
- Possibility of injection flaws (SQL, XSS)
- Misconfigurations in security implementation
- Issues in input validation techniques
- Errors in the interaction of databases
- Lack of proper authentication
- Broken access controls
- Flaws in the logic of applications
Methodology of web app pen-testing
A typical penetration testing procedure for web applications may be authenticated, unauthenticated, or both. Authenticated testing implies receiving credentials to test certain components, while unauthenticated testing is any content that’s not visible to the tester (unless gained through exploiting the vulnerability). Both kinds of testing are equally important because vulnerabilities pop up in both situations, presenting different problems. For example, if SQL injection is present on a webpage that requires user credentials to log on, the tester wouldn’t be able to view this without logging in.
Beyond this, let’s look at the usual steps involved in such a procedure:
1. Define the scope
Before conducting any procedure, it’s important to outline your expectations and goals from the process. This will help you to gain the results you require without wasting time and/or resources. Under this step, you select the websites, related applications and resources that require a proper testing strategy to test for security effectiveness. You will also need to finalize the systems involved and the testing methods needed.
Also called the ‘intelligence gathering’ process, this step provides the necessary information (also depending on the testing method chosen). This includes networks, domain names, mail servers, etc. and different categories of technical and security-based information. It gives a better understanding of the system background and its possible vulnerabilities regarding the website and applications in scope.
3. Scanning for vulnerabilities
This can be taken as an initial step in the vulnerability assessment process, where you analyze the system on its surface and conduct preliminary checks. Then, we can understand how the system potentially responds to an attack, the kind of detailed response, and any remediation suggestions.
This particular step can involve both static and dynamic analysis. The former allows you to check the respective code to see how it may respond to a particular situation while running. Static analysis is usually completed in one run as tools can go through the entire code at this time. Dynamic analysis, on the other hand, is a more practical but time-consuming process. As the name suggests, it looks into the code in real-time while it’s running to get an idea of its performance.
This is when the testing team should use prior information and expertise to glean the possible vulnerabilities hidden within the system.
4. Access and exploitation
Now that we have an idea of the weaknesses and loopholes, it’s time to exploit the system. Experienced testers simulate various attacking scenarios, such as SQL injection attacks, cross-site scripting, installing backdoors, etc. They then exploit these weaknesses, by attempting to place malicious code, gaining unauthorized privileges, manipulating website traffic, and stealing data.
Another important step is to keep the attack alive within the system as long as possible since the persistence in itself is a form of attack. It gives the hacker in-depth access to the system and allows to test its security efficiency in detecting the threats.
5. Final steps
The most important step when debriefing about the entire process is the preparation of the report of the system, its vulnerabilities, and other features. Everything should be presented in an easily understandable manner to those in the technical and non-technical fields. This is so that all stakeholders of the organization are aware of the business impact of such a situation and the remediation measures suggested for the same.
Other important information that should be mentioned includes
- the sensitive data accessed during the testing,
- the vulnerabilities exploited, and
- details on the persistence of threats
There are many more details related to the security testing of web applications since each business has its own requirements and interests.