The Complete OWASP Web Security Testing Guide [Version 4.1] 2022

The Complete OWASP Web Security Testing Guide [Version 4.1] 2022


Today, software development and security testing have become a significant technical challenge. The immense rise of web applications that enable businesses, networking, etc., requires a robust approach for writing and securing the internet, web applications, and data. OWASP and OWASP top 10 are essential in securing web applications and data.


Security testing is essential when developing web applications. However, many organizations overlook this integral component of the Software Development Life Cycle (SDLC). This OWASP Web Security Testing Guide covers the OWASP testing framework, its scope, the principles of successful testing, and its techniques. It also covers reporting best practices and testing for specific vulnerabilities via code inspection and penetration testing.


What is OWASP?

The Open Web Application Security Project (OWASP) is a non-profit organization dedicated to web application and software security. The OWASP guide helps set a security standard for developers and practitioners worldwide. They can use the OWASP standard as guidelines for security testing and code review while developing web applications.


The OWASP offerings, including everything from online tools and videos to forums and events, are free and easily accessible through its website. It sets forward an “open community” model under which anyone can participate and contribute to OWASP-related online chat, projects, etc.


Why is OWASP important?

Creating a guide like this that covers all the crucial aspects of SLDC security is an undertaking task and requires the expertise of people around the world. One of the crucial factors of the OWASP guide is that it is open and easily accessible for anyone involved in the web application development process.


It captures the consensus of leading experts around the world, and the OWASP community can evolve and expand with the increasingly evolving application security threat landscape. It helps guide developers and practitioners on how to perform security testing quickly, effectively, and efficiently. 


Among the main benefits of OWASP, we can highlight the following:


  • Secured applications against cyber attacks
  • Reductions of errors and operational failures in the system
  • Increased chances of application success
  • Stronger encryption methods
  • Enhanced brand reputation


Following the OWASP guide is essential for anyone involved in web application development. Different roles in the organizations can use this guide:


  • Developers can use this guide to ensure secure code production.
  • Software testers and QA to expand test use cases for testing applications.
  • Security specialists to identify gaps in security testing of applications.


While this guide covers different techniques to identify security holes, it should not be considered a complete checklist as new vulnerabilities are always popping up, and organizations can use this guide as a good place to start. 

What is OWASP top 10?

The OWASP Top 10 report consists of the ten most critical web application security risks. The image above highlights the new installment of the OWASP Top 10 2021 report. This list includes the most recent update that occurred in 2021.

According to the new list, three new categories have been added. The risks added are ranked based on security defects, their frequency to occur, the severity of vulnerabilities, and potential impacts. Developers and security practitioners can use this report to get an insight into the most prevalent security risk so that they can minimize the presence of known risks as much as possible while developing web applications.


1. Broken Access Control (A01:2021)
Moved to number 1 from number 5 in the 2021 report based on severity, broken access control is among the top security weaknesses that can aid in accessing user accounts by attackers. This risk had more occurrences in the applications than in any other category.


2. Cryptographic Failures (A02:2021)
Previously known as sensitive data exposure, shifts up to 2nd position depicting failures related to cryptography. This category sheds light on the risk when sensitive data is exposed and compromised during application development.


3. Injection (A03:2021)
Injection falls to number 3 from number 1, comprising cross-site scripting as part of this category. It occurs when an attacker injects an invalid data code into a web application to make it do something it was not designed to do.


4. Insecure Design (A04:2021)
Insecure design is a new category added to the OWASP top 10 2021 report and focuses on risks related to design flaws. For an industry trying to “shift left”, threat modeling, secure design patterns, and principles may not be enough.


5. Security Misconfiguration (A05:2021)
Unsurprisingly, security misconfiguration moves up to the number 5 position as “90% of applications were tested for some form of misconfiguration. It occurs from configuration errors or shortcomings. XML External Entities (XXE) is being added to this category now.


6. Vulnerable & Outdated Components (A06:2021)
Previously known as using components with known vulnerabilities, vulnerable and outdated components move up from number 9 to 6 and focus on the components underlying known and potential risks. Also, outdated components must be evaluated for risks.


7. Identification & Authentication Failures (A07:2021)
Previously known as broken authentication, this category has shifted from number 2 to 7 but remains an integral part of the OWASP Top 10. It includes CWEs related to identification failures that result in compromised passwords, keywords, and sessions, leading to identity theft.


8. Software & Data Integrity Failures (A08:2021)
Introduced as a new category in 2021, it highlights assumptions without verifying integrity related to software updates, critical data, and CI/CD pipelines. Insecure deserialization is now a part of this category.


9. Security Logging & Monitoring Failures (A09:2021)
Previously known as Insufficient Logging and Monitoring, this category has shifted up from number 10 to 9 and includes more types of failures that are challenging to test and aren’t represented in the CVE/CVSS data. Failure in this category can result in more severe compromising activities.


10. Server-side Request Forgery (A10:2021)

Added as a new category in the OWASP Top 10 2021, Server-side Request Forgery (SSRF) focuses on the severity and incidence of SSRF attacks. 


The OWASP Testing Project

The OWASP Testing Project is built with the expertise of leading experts from all around the world. The main goal of this testing framework is to provide knowledge about when, how, where, what, and why of testing the security of web applications.


You can use this framework and adjust it according to your testing requirements. It helps organizations test web applications to build secure software. Go through the complete guide to have a better insight into the OWASP testing framework


Principles of Testing

The OWASP Testing Project clears some significant misconceptions about developing a testing methodology. It puts forward some basic testing principles for professionals when performing security tests on software.


  • There is no silver bullet
    While it may look tempting to secure applications using security scanners and firewalls against attacks, there is no silver bullet for insecure software. The application of security assessment software may be useful, but it may not provide complete security analysis and in-depth test coverage.
  • Think strategically, not tactically
    Previously, security professionals used to follow the patch-and-penetrate model for security testing. It involved fixing bugs but without proper investigations of the root cause. This technique has become outdated. Security professionals should build security in the Software Development Life Cycle and think strategically to prevent the recurrence of security issues.
  • The SLDC is King

    Developers are well aware of the Software Development Life Cycle. It is essential to integrate security into each phase of the SLDC. While every organization has its individual methods and phases of an SDLC model, it must consider different security applications for each conceptual phase to make them a part of the existing process.
  • Test early & test often
    This will help detect security bugs early in the SDLC and at a lower cost. For this, organizations must educate their development and QA teams about security issues and how they can implement different security measures in the SDLC to detect and prevent security attacks.
  • Test Automation
    Leverage dynamic application security testing (DAST), static application security testing (SAST), and software composition analysis (SCA), or dependency tracking tools for standard automated test workflows in modern development methodologies to maintain security information and vulnerabilities in the development process.
  • Understand the scope of security
    Understanding the scope of security is crucial for app development. Knowing the amount of security a given project will require can help protect assets by giving a classification (e.g, sensitive, secret, top-secret, confidential, etc.) that will state how you can handle data.Different regulations also help understand what needs to be followed and how you can implement security for web applications. For example, Directive 96/46/EC4 and Regulation (EU) 2016/679 (General Data Protection Regulation) restrict organizations to handle customer data securely, whatever the application. 
  • Develop the right mindset
    While looking for gaps in the security system, developing the right mindset is very crucial for secure app development. It requires an “out of the box” mindset to think like an attacker and go beyond what is expected. Each web application is developed uniquely and requires security testing accordingly.
  • Use the right tools
    The right tools can play a critical role in efficient security testing. While there is no silver bullet to the problem, selecting the right tools can help you automate many routine security tasks. However, depending entirely on the use of tools is not good. One should understand their usage and integrate them into the system accordingly.
  • The Devil is in the Details
    A superficial review of an application can instill false confidence in its security and can be dangerous. Look out for the correct findings and security gaps. Report and verify every action taken in every possible aspect of the application security is tested.
  • Use source code when available
    Black-box penetration tests may not be as effective and efficient in securing applications as they may seem. Security staff can use the source code while reviewing applications. It can help them identify vulnerability in the application source.
  • Develop metrics
    Organizations must develop metrics to reveal the application security trends. Consistent metrics can help organizations understand:

    • If there is a need for more education or security training for the staff.
    • If there is anything in the security mechanism not understood by the development teams.
    • If the security issues are decreasing with time or not.

    Metrics are not easy to develop. However, using a standard such as the IEEE can prove to be beneficial in the start. 

  • Document the test results
    It is as crucial to document the test results as to perform them. The record must include the tests taken, by whom, when the tests were performed, and the details of security findings during the tests. Moreover, the report must be clear for the business owners to identify gaps in the security system.

Testing Techniques

Organizations can adopt different testing techniques to build security testing programs according to their requirements. In this section, we will mention four techniques along with their advantages and disadvantages.


Manual inspections and reviews

Manual inspections are human reviews that play an essential role in testing security techniques in the organization. They help analyze the people, policies, processes, and technology decisions with the help of documentation and interviews. 


Manual inspections are one of the powerful and effective testing techniques that help by asking people different questions at different levels of testing. It can help understand whether people follow security measures, understand security protocols, or have the skills to design secure applications or not. 


However, a trust-but-verified model must be adopted as nothing told to the reviewer can be accurate, and there are chances of errors. 



  • Flexible
  • Early in the SDLC
  • Promotes teamwork
  • Requires no hard and fast technology


  • Time-consuming
  • Requires human skills and thought to be effective


Threat Modeling

Threat modeling is a technique designers use to predict threat attacks or how malicious attackers can harm the application or computer system. It is a cost-effective method to integrate security in the design phase (can be implemented in other phases too) of SDLC. All applications must develop and document a threat model. 


OWASP recommends taking an approach that simply follows the NIST 800-30 standard for risk assessment. This approach will involve:


  • Decomposing the application 
  • Defining and classifying the assets 
  • Exploring potential vulnerabilities
  • Exploring potential threats
  • Creating mitigation strategies



  • Flexible 
  • Help prioritize threats early in SDLC
  • Risk control



  • Difficult to break down threats and predict actual risk
  • A good threat model may not always lead to good software.


Source Code Review

Source code review is a process of examining the source code of web applications to identify security errors in it. Testing web applications require the availability of the source code for testing purposes. This technique is most liked by experts. They agree on the fact all necessary information is present in the code and can help identify security vulnerabilities. 


According to OWASP experts, any other form of analysis or testing can not detect serious security issues better than this technique. Many problems are hard to discover with other methods.



  • Fast and reliable
  • Competent and effective
  • Provides accuracy



  • High project implementation cost
  • Highly skilled security developers are required
  • Unable to detect runtime errors easily


Penetration testing

Also known as black-box testing or ethical hacking, penetration testing is a technique to test networks or applications for security vulnerabilities. In this technique, the penetration test team acts as the user of applications, and the tester attacks the system or application to exploit security vulnerabilities. 


While penetration testing is an effective technique for networks, it may not prove to be beneficial in application security. Also, organizations must not use it as a stand-alone technique for security issues. “In practice, a penetration test can only identify a small representative sample of all possible security risks in a system.” wrote Gary McGraw in Software Penetration Testing.



  • Fast and cheap
  • Identify and resolve security vulnerabilities
  • Can be handled with a lower skill set than source code review



  • Happen too late in SDLC
  • Above the surface-only testing 


The Need For a Balanced Approach

With so many security testing techniques and processes for web applications, it sometimes becomes challenging to choose a proper technique and determine when to use it. There are no right or wrong techniques for security testing; instead, every phase of SDLC requires a different technique.


While there are different processes for each phase, organizations mostly rely on penetrating testing that may not be enough for web application security. No single technique is enough to address and resolve security vulnerabilities. 


The right approach for security testing is a balanced approach consisting of several techniques. From manual review to source code review to CI/CD pipeline testing, a balanced approach must include testing at all phases of the SDLC. 


There will be times and situations where only one process will be possible. Also, security testing techniques vary in different projects. The following image consists of the right proportion of test efforts according to test techniques in the SDLC.

Deriving Security Test Requirements 

You must know the testing objectives to have a successful security testing program. Security requirements specify these objectives. In this section, we will discuss the testing objective and how you can document requirements by deriving them from applicable standards and regulations. 


Testing Objectives

One of the objectives of security testing is the validation of security control if they work as expected or not. Security requirements help document the functionality of the security control. Another objective of security testing is to implement security controls with no or few vulnerabilities. The OWASP Top 10 mentions some of these vulnerabilities and other vulnerabilities identified previously during risk assessments in the SDLC. 


Understanding business requirements is necessary to document security requirements. For example, if any business wants to provide financial services or deals with online transactions, the security section for its services will highlight the need to secure customer data. Also, the need to comply with applicable security standards or regulations.


Compliance with regulatory industry standards is the first step towards achieving security. For instance, a company that handles credit card data of customers needs to comply with the PCI-DSS regulation. According to this regulation, any company handling credit card information can’t store PINs and CCV2 data. 


These regulations are necessary for companies handling customer data and require security validation via testing and documentation.