Full Title or Meme
- The Context in which an Attestation of Security applies is typically during the Validation of the security protection provided to User secrets (such as Credentials) on a User Device.
- NIST 800-63-3 defines an Attestation as information conveyed to the verifier regarding a directly-connected authenticator or the endpoint involved in an authentication operation. Information conveyed by attestation MAY include, but is not limited to:
- The provenance (e.g., manufacturer or supplier certification), health, and integrity of the authenticator and endpoint.
- Security features of the authenticator.
- Security and performance characteristics of biometric sensor(s).
- Sensor modality.
- When a secure operation is performed at a user location, the packet returned from that User Device needs to be trusted by the Site that receives it.
- The signing key for that packet from a User Device will have a certificate that binds that signing key to a particular device.
- If the device reports a serial number, or (equivalently) a public key that is unique that that device, that can be used as a tracking number for the owner of the device.
- In 1999 Intel started to ship Pentium Processors with a serial number that created huge public outcry about the privacy implications. They backtracked a lot from their original assertions about security an privacy with a Q&A for their OEMs to address the issues. No company has tried putting a serial number in processors since then.
- The certificate for the signing key from the User Device, and potentially the configuration information from the device, will need to be Attested by some Trusted Third Party.
- It is recommended that a large number (ca 100,000) devices be equipped with the same public key to avoid privacy concerns. Then the public key is basically the Identifier for the category of User Device.
- Attestation can be complex for programmable computers with a TPM, or simple for one function User Devices like Security Tokens.
- An example of a single attestation program with associated metadata is described in the FIDO web site.
- When a simple certificate is used, it typically is accompanied by a metadata statement, an example is this one at Yubico.
- Andrew Thomas, Intel Processor Serial Number Q&A for OEMs. (2000-05-04) https://www.theregister.co.uk/2000/05/04/intel_processor_serial_number_q/
- FIDO TechNotes, The Truth about Attestation. (2018-07-19) https://fidoalliance.org/fido-technotes-the-truth-about-attestation/