WorkerGlobalScope: crypto property

The crypto read-only property of the WorkerGlobalScope interface returns the Crypto object for this worker. This object gives workers access to certain cryptographic related services.

Although the property itself is read-only, all of its methods (and the methods of its child object, SubtleCrypto) are not read-only, and therefore vulnerable to attack by polyfill.

Although crypto is available on all workers, the returned Crypto object only has one usable feature in insecure contexts: the getRandomValues() method. In general, you should use this API only in secure contexts.