The HTTP Content-Security-Policy response header allows web site administrators to control resources the user agent is allowed to load for a given page. With a few exceptions, policies mostly involve specifying server origins and script endpoints. This helps guard against cross-site scripting attacks (XSS).

For more information, see also this article on Content Security Policy (CSP).

Syntax

Content-Security-Policy: <policy-directive>; <policy-directive>

Directives

Fetch directives

Fetch directives control locations from which certain resource types may be loaded.

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