AuthenticatorAssertionResponse.signature

Secure context
This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The signature read-only property of the AuthenticatorAssertionResponse interface is an ArrayBuffer object which is the signature of the authenticator for both AuthenticatorAssertionResponse.authenticatorData and a SHA-256 hash of the client data (AuthenticatorAssertionResponse.clientDataJSON).

This signature will be sent to the server for control, as part of the response. It provides the proof that an authenticator does possess the private key which was used for the credential's generation.

Note: An AuthenticatorAssertionResponse instance is available on PublicKeyCredential.response after calling navigator.credentials.get().

Note: This property may only be used in top-level contexts and will not be available in an <iframe> for example.

Syntax

signature = authenticatorAssertionResponse.signature

Value

An ArrayBuffer object which the signature of the authenticator (using its private key) for both AuthenticatorAssertionResponse.authenticatorData and a SHA-256 hash given by the client for its data (the challenge, the origin, etc. and available from AuthenticatorAssertionResponse.clientDataJSON).

Examples

var options = {
  challenge: new Uint8Array(26), // will be another value, provided by the relying party server
  timeout: 60000
};

navigator.credentials.get({  publickey: options })
  .then(function (assertionPKCred) {
    var signature = assertionPKCred.response.signature;

    // Send response and client extensions to the server so that it can
    // go on with the authentication
    
}).catch(function (err) {
   console.error(err);
});

Specifications

Specification Status Comment
Web Authentication: An API for accessing Public Key Credentials Level 1
The definition of 'signature' in that specification.
Candidate Recommendation Initial definition.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
signatureChrome Full support 67
Full support 67
Full support 65
Notes Disabled
Notes Only supports USB U2F tokens.
Disabled From version 65: this feature is behind the Web Authentication API preference (needs to be set to Enabled). To change preferences in Chrome, visit chrome://flags.
Edge Full support 18Firefox Full support 60
Notes
Full support 60
Notes
Notes Only supports USB U2F tokens.
IE No support NoOpera No support NoSafari No support NoWebView Android Full support 70Chrome Android Full support 70Edge Mobile ? Firefox Android Full support 60
Notes
Full support 60
Notes
Notes Only supports USB U2F tokens.
Opera Android No support NoSafari iOS No support NoSamsung Internet Android ?

Legend

Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown
See implementation notes.
See implementation notes.
User must explicitly enable this feature.
User must explicitly enable this feature.

Document Tags and Contributors

Contributors to this page: mdnwebdocs-bot, SphinxKnight
Last updated by: mdnwebdocs-bot,