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API Security Headers

It's crucial to understand the importance of HTTP security headers, especially when it comes to API security. HTTP security headers are additional values sent by a web server along with a web page or API response. These headers provide important security features and protections for both the server and the client.

API Content Security Policies (CSP)

CSP headers define the allowed sources for various types of content, such as scripts, stylesheets, and images. Implementing CSP for APIs helps mitigate the risks of cross-site scripting (XSS) attacks by specifying which domains are allowed to execute scripts or load resources, reducing the attack surface.

TODO: List CSP HTTP Headers for security. Add risk example

API Cross-Origin Resource Sharing (CORS)

CORS headers control access to resources from different origins. For APIs, proper CORS configuration ensures that only trusted domains can access the API resources, preventing unauthorized access from potentially malicious websites.

TODO: Add CORS HTTP Header example for security. Add risk example

HTTP Strict Transport Security (HSTS)

HSTS headers instruct the browser to always use HTTPS when communicating with the server, even if the user types "http" in the address bar. This prevents man-in-the-middle attacks and ensures that all data exchanged between the client and the server is encrypted, enhancing the confidentiality and integrity of API communications.

TODO: Add HTTP Header and risk example.


This header prevents browsers from MIME-sniffing a response away from the declared content type, which can help prevent certain types of attacks, such as content type confusion attacks.

TODO: Add HTTP Header and risk example.


X-Frame-Options header protects against clickjacking attacks by preventing the API response from being embedded within a frame or iframe on another domain.

TODO: Add HTTP Header and risk example.

X-XSS-Protection (deprecated)

This header enables a built-in reflective XSS filter in modern web browsers, providing an additional layer of protection against certain types of XSS attacks.

TODO: Add HTTP Header and risk example.

X-Permitted-Cross-Domain-Policies (deprecated)

This header specifies the policy file that governs how Flash and Adobe AIR applications can interact with the API resources across different domains.

TODO: Add HTTP Header and risk example.