The OWASP Top 10 is the most widely recognised list of critical web application security risks. If you run a web application, SaaS platform, or API, these are the vulnerabilities you need to know about.

What Is OWASP?

The Open Worldwide Application Security Project (OWASP) is a non-profit foundation that works to improve software security. Their Top 10 list is updated periodically and represents the most critical security risks to web applications, based on real-world data.

The OWASP Top 10 (2021)

A01: Broken Access Control - Users can act outside their intended permissions, viewing other users' data or accessing admin functions. This is the #1 vulnerability we find in penetration tests, and it leads directly to data breaches.

A02: Cryptographic Failures - Sensitive data exposed due to weak or missing encryption: passwords stored in plain text, data transmitted without TLS, weak hashing.

A03: Injection - Untrusted data sent to an interpreter as part of a command or query. SQL injection is the most famous, but command, LDAP, and NoSQL injection all fall here.

A04: Insecure Design - Fundamental design flaws that can't be fixed by a perfect implementation, such as missing threat modelling or insecure business logic.

A05: Security Misconfiguration - Default configurations, unnecessary features enabled, missing security headers, verbose error messages.

A06: Vulnerable and Outdated Components - Using libraries, frameworks, or components with known vulnerabilities.

A07: Identification and Authentication Failures - Weaknesses in authentication: weak passwords allowed, missing brute-force protection, session tokens that don't expire.

A08: Software and Data Integrity Failures - Code and infrastructure that doesn't verify integrity, such as insecure CI/CD pipelines.

A09: Security Logging and Monitoring Failures - Insufficient logging and alerting. If you can't detect an attack, you can't respond to it.

A10: Server-Side Request Forgery (SSRF) - An application fetches a remote resource based on user input without validation, letting attackers reach internal services.

What Should You Do?

Get tested - a penetration test aligned to the OWASP Top 10 will tell you exactly where you stand. Prioritise fixes based on business impact, not just severity score. And build securely from the start - training your developers on secure coding practices is cheaper than remediation after the fact.

How We Can Help

Every penetration test we run includes full OWASP Top 10 coverage. We test for all ten categories, report findings with business impact context, and provide code-level remediation guidance.

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