The OWASP API Security Top 10 is a list of the top 10 most common security risks for APIs (Application Programming Interfaces). APIs allow different software systems to communicate with each other and exchange data. The following is a summary of the OWASP API Security Top 10, along with examples:

  1. Broken object level authorization: This occurs when an API does not properly enforce access controls, allowing unauthorized users to access sensitive data. For example, an API that allows users to retrieve personal information about other users without proper authorization.
  2. Broken authentication: This occurs when an API does not properly authenticate users, allowing unauthorized users to gain access to sensitive data. For example, an API that uses weak or easily guessable passwords for user authentication.
  3. Excessive data exposure: This occurs when an API exposes too much data, potentially allowing unauthorized users to access sensitive information. For example, an API that exposes sensitive customer data, such as credit card numbers or social security numbers, without proper authorization.
  4. Lack of resources & rate limiting: This occurs when an API does not properly limit the number of requests that can be made to it, potentially allowing attackers to overwhelm the system with too many requests. For example, an API that does not have rate limiting in place to prevent a denial of service (DoS) attack.
  5. Broken function level authorization: This occurs when an API does not properly enforce access controls at the function level, allowing unauthorized users to access sensitive data or perform actions they should not be able to. For example, an API that allows users to delete other users’ accounts without proper authorization.
  6. Mass assignment: This occurs when an API allows users to submit data that can be used to modify object properties, potentially allowing attackers to modify sensitive data. For example, an API that allows users to submit data that can be used to change their account privileges.
  7. Security misconfiguration: This occurs when an API has insecure default configurations or is improperly configured, potentially allowing unauthorized access to sensitive data. For example, an API that has debug mode enabled in production, allowing attackers to view sensitive data.
  8. Injection: This occurs when an API does not properly sanitize user input, potentially allowing attackers to inject malicious code into the system. For example, an API that does not properly sanitize user input and is vulnerable to SQL injection attacks.
  9. Improper error handling: This occurs when an API does not properly handle errors, potentially exposing sensitive information or allowing attackers to exploit vulnerabilities. For example, an API that returns detailed error messages that reveal sensitive information about the system.
  10. Insufficient logging & monitoring: This occurs when an API does not properly log and monitor activity, making it difficult to detect and respond to security incidents. For example, an API that does not log failed login attempts, making it difficult to detect and respond to brute force attacks.

It’s important to note that these are just examples, and the specifics of an API’s security risks will depend on its design and implementation. To mitigate these risks, it’s important to follow best practices for API security, including proper authentication and authorization, input validation, and error handling, as well as regularly testing and monitoring the API for vulnerabilities.