Element: securitypolicyviolation event

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since August 2016.

The securitypolicyviolation event is fired when a Content Security Policy is violated.

The event is fired on the element when there is a violation of the CSP policy.

This event bubbles and is composed. It is normally handled by an event handler on the Window or Document object.

Note: You should add the handler for this event to a top level object (i.e. Window or Document). While the property exists in HTML elements, you can't assign a handler to the property until the elements have been loaded, by which time this event will already have fired.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("securitypolicyviolation", (event) => {});

onsecuritypolicyviolation = (event) => {};

Event type

A SecurityPolicyViolationEvent. Inherits from Event.

Examples

The code below shows how you might add an event handler function using the onsecuritypolicyviolation global event handler property or addEventListener() on the top level Window (you could use exactly the same approach on Document).

Note: The example doesn't assign the handler directly to an element because, as noted above, for elements defined in HTML, the event would fired before this code could run. You might however add the event listener directly to an element that is dynamically constructed!

window.onsecuritypolicyviolation = (e) => {
  // Handle SecurityPolicyViolationEvent e here
};

window.addEventListener("securitypolicyviolation", (e) => {
  // Handle SecurityPolicyViolationEvent e here
});

Specifications

Specification
Content Security Policy Level 3 # eventdef-globaleventhandlers-securitypolicyviolation
HTML Standard # handler-onsecuritypolicyviolation

Browser compatibility

BCD tables only load in the browser