OWASP API Security Top 10
The ten most critical vulnerabilities in APIs
The OWASP API Security Top 10 is a worldwide reference list documenting the most critical and frequent categories of vulnerabilities specifically in APIs, distinct from the traditional OWASP Top 10 for web applications because APIs present their own risk patterns, such as object- and function-level authorization failures, excessive data exposure or mass assignment of properties. Its practical value lies in prioritizing security effort toward where incidents actually happen, since the evidence gathered by OWASP shows that the vast majority of API breaches are due to authorization logic failures, not sophisticated technical vulnerabilities such as code injection. For a development team, using this list as a checklist during design and code review is much more effective than relying only on an automated scanner at the end of the cycle, because several of these categories, such as BOLA or unrestricted resource consumption, depend on business context and aren't detected with generic signatures. Knowing it thoroughly is the mandatory starting point before diving into any specific API security control.