Method, apparatus, and computer-readable medium for searching polymorphically encrypted data

A method executed by one or more computing devices for searching polymorphically encrypted data, the method comprising:

• storing, by at least one of the one or more computing devices, one or more pseudonymous tokens in a data store, the one or more pseudonymous tokens being generated by encrypting a ciphertext using a first algorithm and an encryption key, the first algorithm comprising a polymorphic algorithm configured to generate a distinct pseudonymous token for each application of the polymorphic algorithm and the same encryption key to the same ciphertext;
• and
• identifying, by at least one of the one or more computing devices, data in the data store that corresponds to the ciphertext by querying the data store using a search token generated by encrypting the ciphertext using a second algorithm and the encryption key, the search token being distinct from the one or more pseudonymous tokens.