What is the OWASP Top 10?

Introduction to OWASP

OWASP, which stands for the Open Web Application Security Project, is a nonprofit online community dedicated to improving web application security. It does this by providing free and openly available resources in the form of tools, documentation, and community-driven projects directly from its website to help organisations and individuals with IoT, system software, and web application security.

Their most famous project is the OWASP Top Ten.

What is the OWASP Top Ten?

The OWASP Top Ten lists the most critical web application security risks. It was developed for web app developers, security professionals, and penetration testers and is updated every three to four years. It serves as a guide for improving security practices, raising awareness, and protecting against frequent threats in web applications. The most recent edition was released in 2021, and the next edition is expected to be released in 2025.

How is the OWASP Top Ten Determined?

The OWASP Top Ten is determined through a combination of data analysis on the most common web app vulnerabilities and their average severity, input from cybersecurity experts and community feedback. 

OWASP regularly collects and analyses real-world data on web app vulnerabilities and emerging cybersecurity threats, consulting with security professionals and industry experts to identify and rank the most critical risks. 

To check up on OWASP’s progress for the upcoming OWASP Top Ten 2025, click here. 

The OWASP Top Ten List

It’s important to remember that the list is not ranked in order of importance, and OWASP emphasises that all the listed risks are critical and should be addressed promptly. 

Here is the OWASP Top Ten with a breakdown as to what each item means.

A01 Broken Access Control

Due to misconfigured access controls, unauthorised users can gain access to data or actions that are supposed to be restricted. This allows attackers to bypass permissions and exploit system flaws to retrieve or manipulate sensitive data. 

A02 Cryptographic Failures

This involves failing to properly protect sensitive data through cryptography. Issues include using outdated algorithms, improper key management, or failing to encrypt critical data, leaving it exposed to unauthorised access and tampering.

A03 Injection

Injection flaws occur when untrusted data is sent to an interpreter as part of a command or query. Examples include SQL, NoSQL, OS, and LDAP injection. These flaws allow attackers to execute arbitrary code or commands, potentially accessing sensitive information or compromising the entire application.

A04 Insecure Design

This refers to flaws and vulnerabilities resulting from poor design decisions and a lack of secure development practices. Examples include inadequate threat modelling, a lack of security controls in design, and failure to consider security implications in the architecture phase.

A05 Security Misconfiguration

These are errors in the configuration of security settings in applications, frameworks, servers, and databases. Misconfigurations can lead to default accounts, unpatched flaws, overly verbose error messages, and unsecured directories, making it easy for attackers to exploit the system.

A06 Vulnerable and Outdated Components

Using outdated or vulnerable software libraries, frameworks, and other components can expose applications to known vulnerabilities. To protect against attacks, it is essential to keep all components up to date and patch known vulnerabilities.

A07 Identification and Authentication Failures

Issues in the authentication process, such as weak passwords, ineffective session management, and flawed multi-factor authentication, can allow attackers to impersonate legitimate users and gain unauthorised access to the application.

A08 Software and Data Integrity Failures

This includes vulnerabilities in software supply chains, such as trusting unverified components or improper update mechanisms. It can lead to unauthorised code execution, malicious updates, and data tampering, impacting the integrity of the software and data.

A09 Security Logging and Monitoring Failures

Inadequate logging and monitoring can prevent timely detection and response to security incidents. Without proper logs, detecting breaches, tracing attacker actions, and performing forensic analysis becomes challenging, increasing the risk and impact of attacks.

A10 Server-Side Request Forgery (SSRF)

SSRF flaws occur when a server can be tricked into making requests to unintended locations. Attackers can exploit SSRF to access internal systems, retrieve sensitive data, or perform other malicious actions by manipulating server requests.

How to Use the OWASP Top Ten?

Effective use of the OWASP Top Ten differs depending on who you are. 

It is there for developers to understand and learn about the top vulnerabilities, help them follow best practices to minimise risk and prompt them to review code regularly for potential issues.

IT managers use it to help them create policies that address these vulnerabilities, ensure team members are trained on the OWASP Top Ten, and schedule regular audits to check for compliance and vulnerabilities.

The list can be used as a guide for penetration testers to test applications and provide actionable advice based on the vulnerabilities found.

Benefits of Using the OWASP Top Ten

Using the OWASP Top Ten has several benefits, but for this article, we’ll focus on three.

Risk Awareness

By highlighting the most critical security risks, the OWASP Top Ten helps to increase awareness of cybersecurity threats among developers, managers and security professionals.

Improved Security Practices

The OWASP Top Ten can be used to guide the implementation of best practices and security controls, helping to mitigate common and severe vulnerabilities. 

Compliance

Following the OWASP Top Ten assists in meeting industry security standards and compliance requirements, regardless of what industry you’re in.

Misconceptions Regarding the OWASP Top Ten

Despite being a fantastic tool for education and web app development, some common misconceptions need to be addressed. 

These Are All the Web App Vulnerabilities

The most prominent misconception is that the OWASP Top Ten covers all possible security risks and that to develop a secure web application, you only have to protect against these ten threats. 

While the OWASP Top Ten highlights the most critical and common vulnerabilities, it certainly does not cover all vulnerabilities. When developing your web app, you should look to protect against more vulnerabilities than just those ten highlighted in the list. 

Testing Once is Enough

There’s a belief that addressing the OWASP Top Ten vulnerabilities once ensures ongoing security.

Security threats evolve, and new vulnerabilities emerge. Continuous assessment, updating security practices, and staying informed about the latest threats is essential. The Top Ten should be part of an ongoing security program, not a one-time checklist.

All You Have to Do is Read the List

Translating the OWASP Top Ten’s general guidance into specific actions can be difficult in varied and complex environments. It certainly isn’t as simple as reading the list and saying, just follow the instructions. 

Implementing the recommended controls and practices requires tailoring to fit the unique needs and requirements of each organisation. This can involve significant effort in terms of resources, training, and changes to existing workflows, making it challenging to execute effectively.

Conclusion

In this article, we’ve learnt that OWASP, the Open Web Application Security Project is a nonprofit community-driven organisation that develops projects like the OWASP Top Ten to improve web app security. 

Their top ten list is an educational tool that is updated every three to four years and highlights the most critical and common web app vulnerabilities. 

While the list doesn’t include all web app vulnerabilities and should be checked regularly, its ability to help reduce the risk of cyberattacks on web applications and improve compliance makes it a tool every web app developer should know.