US Patent 11405191 Guaranteed encryptor authenticity

Embodiments described herein provide cryptographic techniques to enable a recipient of a signed message containing encrypted data to verify that the signer of the message and the encryptor of the encrypted data are the same party, or at the least, have joint possession of a common set of secret cryptographic material. These techniques can be used to harden an online payment system against interception and resigning of encrypted payment information.