CSP: frame-src
The HTTP Content-Security-Policy (CSP)
frame-src directive specifies valid sources for nested
browsing contexts loading using elements such as <frame> and
<iframe>.
| CSP version | 1 |
|---|---|
| Directive type | Fetch directive |
| Fallback |
If this directive is absent, the user agent will look for the
child-src directive (which falls back to the
default-src directive).
|
Syntax
One or more sources can be allowed for the frame-src policy:
Content-Security-Policy: frame-src <source>;
Content-Security-Policy: frame-src <source> <source>;
Sources
<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).
Examples
Violation cases
Given this CSP header:
Content-Security-Policy: frame-src https://example.com/
The following <iframe> is blocked and won't load:
<iframe src="https://not-example.com/"></iframe>
Specifications
| Specification |
|---|
| Content Security Policy Level 3 # directive-frame-src |
Browser compatibility
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