CSP: child-src

The HTTP Content-Security-Policy (CSP) child-src directive defines the valid sources for web workers and nested browsing contexts loaded using elements such as <frame> and <iframe>. For workers, non-compliant requests are treated as fatal network errors by the user agent.

One or more sources can be allowed for the child-src policy:

Content-Security-Policy: child-src <source>;
Content-Security-Policy: child-src <source> <source>;

<source> can be any one of the values listed in CSP Source Values.

Note that this same set of values can be used in all fetch directives (and a number of other directives).

Given this CSP header:

Content-Security-Policy: child-src https://example.com/

This <iframe> and worker are blocked and won't load:

<iframe src="https://not-example.com"></iframe>

<script>
  var blockedWorker = new Worker("data:application/javascript,...");
</script>

• Content-Security-Policy
• <frame> and <iframe>
• Worker, SharedWorker, ServiceWorker