CSP: sandbox
The HTTP Content-Security-Policy
(CSP)
sandbox
directive enables a sandbox for the requested
resource similar to the <iframe>
sandbox
attribute. It applies restrictions to a page's actions including preventing popups,
preventing the execution of plugins and scripts, and enforcing a same-origin policy.
CSP version | 1.1 / 2 |
---|---|
Directive type | Document directive |
This directive is not supported in the <meta>
element or by the
Content-Security-policy-Report-Only
header field.
|
Syntax
http
Content-Security-Policy: sandbox;
Content-Security-Policy: sandbox <value>;
where <value>
can optionally be one of the following values:
allow-downloads
-
Allows downloading files through an
<a>
or<area>
element with the download attribute, as well as through the navigation that leads to a download of a file. This works regardless of whether the user clicked on the link, or JS code initiated it without user interaction. allow-downloads-without-user-activation
Experimental-
Allows for downloads to occur without a gesture from the user.
allow-forms
-
Allows the page to submit forms. If this keyword is not used, form will be displayed as normal, but submitting it will not trigger input validation, sending data to a web server or closing a dialog.
allow-modals
-
Allows the page to open modal windows by
Window.alert()
,Window.confirm()
,Window.print()
andWindow.prompt()
, while opening a<dialog>
is allowed regardless of this keyword. It also allows the page to receiveBeforeUnloadEvent
event. allow-orientation-lock
-
Lets the resource lock the screen orientation.
allow-pointer-lock
-
Allows the page to use the Pointer Lock API.
allow-popups
-
Allows popups (like from
Window.open()
,target="_blank"
,Window.showModalDialog()
). If this keyword is not used, that functionality will silently fail. allow-popups-to-escape-sandbox
-
Allows a sandboxed document to open new windows without forcing the sandboxing flags upon them. This will allow, for example, a third-party advertisement to be safely sandboxed without forcing the same restrictions upon the page the ad links to.
allow-presentation
-
Allows embedders to have control over whether an iframe can start a presentation session.
allow-same-origin
-
If this token is not used, the resource is treated as being from a special origin that always fails the same-origin policy (potentially preventing access to data storage/cookies and some JavaScript APIs).
allow-scripts
-
Allows the page to run scripts (but not create pop-up windows). If this keyword is not used, this operation is not allowed.
allow-storage-access-by-user-activation
Experimental-
Lets the resource request access to the parent's storage capabilities with the Storage Access API.
-
Lets the resource navigate the top-level browsing context (the one named
_top
). -
Lets the resource navigate the top-level browsing context, but only if initiated by a user gesture.
-
Allows navigations to non-
http
protocols built into browser or registered by a website. This feature is also activated byallow-popups
orallow-top-navigation
keyword.
Examples
http
Content-Security-Policy: sandbox allow-scripts;
Specifications
Specification |
---|
Content Security Policy Level 3 # directive-sandbox |
Browser compatibility
BCD tables only load in the browser
See also
Content-Security-Policy
-
sandbox
attribute on<iframe>
elements