Abstract: A method is provided for identifying synthetic “deep-fake” audio samples versus organic audio samples. Methods may include: generating a model of a vocal tract using one or more organic audio samples from a user; identifying a set of bigram-feature pairs from the one or more audio samples; estimating the cross-sectional area of the vocal tract of the user when speaking the set of bigram-feature pairs; receiving a candidate audio sample; identifying bigram-feature pairs of the candidate audio sample that are in the set of bigram-feature pairs; calculating a cross-sectional area of a theoretical vocal tract of a user when speaking the identified bigram-feature pairs; and identifying the candidate audio sample as a deep-fake audio sample in response to the calculated cross-sectional area of the theoretical vocal tract of a user failing to correspond within a predetermined measure of the estimated cross sectional area of the vocal tract of the user.

Abstract: Disclosed are various embodiments for detecting Signaling System 7 (SS7) redirection attacks by measuring call audio round trip times between phones. Such redirection attacks force calls to travel longer physical distances than usual, thereby causing longer end-to-end delay. Accordingly, various embodiments implement a distance bounding-inspired protocol that allows for securely characterizing the round trip time between two call endpoints. As a result, telephone users can reliably detect SS7 redirection attacks and protect the information contained in their calls.

Abstract: A method is provided for identifying synthetic “deep-fake” audio samples versus organic audio samples. Methods may include: generating a model of a vocal tract using one or more organic audio samples from a user; identifying a set of bigram-feature pairs from the one or more audio samples; estimating the cross-sectional area of the vocal tract of the user when speaking the set of bigram-feature pairs; receiving a candidate audio sample; identifying bigram-feature pairs of the candidate audio sample that are in the set of bigram-feature pairs; calculating a cross-sectional area of a theoretical vocal tract of a user when speaking the identified bigram-feature pairs; and identifying the candidate audio sample as a deep-fake audio sample in response to the calculated cross-sectional area of the theoretical vocal tract of a user failing to correspond within a predetermined measure of the estimated cross sectional area of the vocal tract of the user.

Abstract: Systems and methods for call authentication are provided. A method can include an enrollment protocol that ensures users control the number they claim to own, a handshake protocol that mutually authenticates the calling parties, and a call integrity protocol that ensures the security of the voice channel and the content it carries. A server can act as either an endpoint or intermediary between user clients and client-server architecture can be employed. All protocols can include end-to-end cryptography and the enrollment protocol can issue a certificate that binds the identity of the client to a phone number.

Abstract: Disclosed are various embodiments for detecting Signaling System 7 (SS7) redirection attacks by measuring call audio round trip times between phones. Such redirection attacks force calls to travel longer physical distances than usual, thereby causing longer end-to-end delay. Accordingly, various embodiments implement a distance bounding-inspired protocol that allows for securely characterizing the round trip time between two call endpoints. As a result, telephone users can reliably detect SS7 redirection attacks and protect the information contained in their calls.

Abstract: Systems and methods for call authentication are provided. A method can include an enrollment protocol that ensures users control the number they claim to own, a handshake protocol that mutually authenticates the calling parties, and a call integrity protocol that ensures the security of the voice channel and the content it carries. A server can act as either an endpoint or intermediary between user clients and client-server architecture can be employed. All protocols can include end-to-end cryptography and the enrollment protocol can issue a certificate that binds the identity of the client to a phone number.