PassKeys decoded attestation has no statement

Hi,

I'm decoding an attestationObject created with ASAuthorizationPlatformPublicKeyCredentialRegistration, but the results have no statement:

{'fmt': 'none', 'attStmt': {}, 'authData': '.....data here.......'}

The whole credentialRegistration.rawAttestationObject is 182 bytes

I'm expecting to see keys like: sig, x5c, alg, certInfo, pubArea etc, but the dictionary is empty, any ideas why it would be empty?

Expected Keys: https://github.com/duo-labs/py_webauthn/blob/9d81f2ea12d247b034714aac73701dce32cd67c8/webauthn/helpers/parse_attestation_statement.py#L4

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hmmm, as noted here: https://developer.apple.com/forums/thread/708982 the engineer states passkeys have no statement...confusing

  • Yep, this is expected. Attestation statements were designed in the spec to attest to specific properties of the authenticator, under the assumption the credential would only live on that one authenticator. When credentials can sync to other authenticators which may have different properties, the current attestation statement design doesn't have a way to express this.

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I've found the key in the authData section