CSP: font-src

The HTTP Content-Security-Policy (CSP) font-src directive specifies valid sources for fonts loaded using @font-face.

CSP version	1
Directive type	Fetch directive
`default-src` fallback	Yes. If this directive is absent, the user agent will look for the `default-src` directive.

Syntax

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

Content-Security-Policy: font-src <source>;
Content-Security-Policy: font-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: font-src https://example.com/

The following font resource loading is blocked and won't load:

<style>
  @font-face {
    font-family: "MyFont";
    src: url("https://not-example.com/font");
  }
  body {
    font-family: "MyFont";
  }
</style>

Specification
Content Security Policy Level 3 # directive-font-src

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`font-src`	25	14	23	No	15	7	Yes	Yes	23	Yes	7	Yes