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CORS

The cross-origin negotiation. A small, closed set of headers that decide whether a browser is allowed to see a response it already received.

13 headers, ordered by how many providers in the catalog declare them.

Access-Control-Allow-Origin 30 providers regulated

A wildcard on an authenticated surface is a data-protection failure anyone can observe without credentials.

Access-Control-Allow-Methods 16 providers

The Access-Control-Allow-Methods HTTP header — cors, declared by 16 providers in the API Evangelist catalog.

Access-Control-Allow-Headers 16 providers

The Access-Control-Allow-Headers HTTP header — cors, declared by 16 providers in the API Evangelist catalog.

Origin 14 providers 2 spellings

The Origin HTTP header — cors, RFC 6454, declared by 14 providers in the API Evangelist catalog.

Access-Control-Allow-Credentials 11 providers

The Access-Control-Allow-Credentials HTTP header — cors, declared by 11 providers in the API Evangelist catalog.

Access-Control-Expose-Headers 4 providers 2 spellings

The Access-Control-Expose-Headers HTTP header — cors, declared by 4 providers in the API Evangelist catalog.

Access-Control-Max-Age 1 providers

The Access-Control-Max-Age HTTP header — cors, declared by 1 providers in the API Evangelist catalog.

Timing-Allow-Origin

The Timing-Allow-Origin HTTP header — cors, not observed in the catalog.

Method-Check

The Method-Check HTTP header — cors, not observed in the catalog.

Method-Check-Expires

The Method-Check-Expires HTTP header — cors, not observed in the catalog.

Access-Control

The Access-Control HTTP header — cors, not observed in the catalog.

Access-Control-Request-Method

The Access-Control-Request-Method HTTP header — cors, not observed in the catalog.

Access-Control-Request-Headers

The Access-Control-Request-Headers HTTP header — cors, not observed in the catalog.