API security is probably one of the most important aspects that you, as a developer, can think of before releasing your API.
Well, our team came up with an API security checklist that can help you tremendously in your process.
This checklist focuses mainly in API security. It can help you track and adopt the most important security countermeasures when designing, testing and releasing your API.
- Don’t use
Basic Auth. Use standard authentication (e.g. JWT, OAuth).
- Don’t reinvent the wheel in
password storage. Use the standards.
Max Retryand jail features in Login.
- Use encryption on all sensitive data.
- Use a random complicated key (
JWT Secret) to make brute forcing the token very hard.
- Don’t extract the algorithm from the payload. Force the algorithm in the backend (
- Make token expiration (
RTTL) as short as possible.
- Don’t store sensitive data in the JWT payload, it can be decoded easily.
- Always validate
redirect_uriserver-side to allow only whitelisted URLs.
- Always try to exchange for code and not tokens (don’t allow
stateparameter with a random hash to prevent CSRF on the OAuth authentication process.
- Define the default scope, and validate scope parameters for each application.
- Limit requests (Throttling) to avoid DDoS / brute-force attacks.
- Use HTTPS on server side to avoid MITM (Man in the Middle Attack).
HSTSheader with SSL to avoid SSL Strip attack.
- Use the proper HTTP method according to the operation:
PUT/PATCH (replace/update), and
DELETE (to delete a record), and respond with
405 Method Not Allowedif the requested method isn’t appropriate for the requested resource.
content-typeon request Accept header (Content Negotiation) to allow only your supported format (e.g.
application/json, etc.) and respond with
406 Not Acceptableresponse if not matched.
content-typeof posted data as you accept (e.g.
- Validate user input to avoid common vulnerabilities (e.g.
Remote Code Execution, etc.).
- Don’t use any sensitive data (
security tokens, or
API keys) in the URL, but use standard Authorization header.
- Use an API Gateway service to enable caching, Rate Limit policies (e.g.
Spike Arrest, or
Concurrent Rate Limit) and deploy APIs resources dynamically.
- Check if all the endpoints are protected behind authentication to avoid broken authentication process.
- User own resource ID should be avoided. Use
- Don’t auto-increment IDs. Use
- If you are parsing XML files, make sure entity parsing is not enabled to avoid
XXE(XML external entity attack).
- If you are parsing XML files, make sure entity expansion is not enabled to avoid
Billion Laughs/XML bombvia exponential entity expansion attack.
- Use a CDN for file uploads.
- If you are dealing with huge amount of data, use Workers and Queues to process as much as possible in background and return response fast to avoid HTTP Blocking.
- Do not forget to turn the DEBUG mode OFF.
Content-Security-Policy: default-src 'none'header.
- Remove fingerprinting headers –
content-typefor your response, if you return
application/jsonthen your response
- Don’t return sensitive data like
- Return the proper status code according to the operation completed. (e.g.
400 Bad Request,
405 Method Not Allowed, etc.).
- Audit your design and implementation with unit/integration tests coverage.
- Use a code review process and disregard self-approval.
- Ensure that all components of your services are statically scanned by AV software before pushing to production, including vendor libraries and other dependencies.
- Design a rollback solution for deployments.
If you’re a GitHub fanatic, you can find our original repository here > Api Security Checklist.