Cryptanalysis and improvement of the YAK protocol with formal security proof and security verification via Scyther

Abstract

Hao proposed the YAK as a robust key agreement based on public-key authentication, and the author claimed that the YAK protocol withstands all known attacks and therefore is secure against an extremely strong adversary. However, Toorani showed the security flaws in the YAK protocol. This paper shows that the YAK protocol cannot withstand the known key security attack, and its consequences lead us to introduce a new key compromise impersonation attack, where an adversary is allowed to reveal both the shared static secret key between two-party participation and the ephemeral private key of the initiator party in order to mount this attack. In addition, we present a new security model that covers these attacks against an extremely strong adversary. Moreover, we propose an improved YAK protocol to remedy these attacks and the previous attacks mentioned by Toorani on the YAK protocol, and the proposed protocol uses a verification mechanism in its block design that provides entity authentication and key confirmation. Meanwhile, we show that the proposed protocol is secure in the proposed formal security model under the gap Diffie-Hellman assumption and the random oracle assumption. Moreover, we verify the security of the proposed protocol and YAK protocol by using an automatic verification method such as the Scyther tool, and the verification result shows that the security claims of the proposed protocol are proven, in contrast to those of the YAK protocol, which are not proven. The security and performance comparisons show that the improved YAK protocol outperforms previous related protocols. K E Y W O R D Sauthenticated key agreement, cryptanalysis, eCK, formal security model, key compromise impersonation, known key security, Scyther tool | INTRODUCTIONAs a result of the rapid development in the Internet of Things (IoT)-related applications in daily life, which uses diverse communication devices, securing data has become a more challenging task. Due to a diverse powerful adversary for revealing secret information from a party's participation via the open communication model, many formal security models and automated verification tools have been developed for finding security flaws in proposed new protocols before implementing them in applications. Consequently, secret key distribution and user authentication became the most important security issues in IoT. Nowadays, the security proof and verification process of an Authenticated Key Agreement (AKA) protocol in the formal security model is important for successful IoT applications.Diffie-Hellman (DH) key exchange protocol is a fundamental building block to distribute a shared secret key over an insecure communication model, 1 which is based on the concept of asymmetric cryptography. The shared secret key is used to provide confidentiality, integrity, nonrepudiation, and authenticity for data during transmission over an untrusted communication model. An AKA protocol is based on a public key, wherein the two intended participating parties exchange static and ephemeral ...

PUFDCA: A Zero-Trust-Based IoT Device Continuous Authentication Protocol

“…Figure 6 indicates the formal verification result of PUFDCA in Scyther. To analyze the result, the Scyther claims were classified into security properties, involving confidentiality, freshness, forward secrecy, and resistance to impersonation and replay attacks [20,21]. The security properties can be analyzed for the proposed solution.…”

An authenticated, secure, and mutable multiple‐session‐keys protocol based on elliptic curve cryptography and text‐to‐image encryption algorithm

“…The YAK protocol achieved robust security under the computational Diffie–Hellman (CDH) assumption in the random oracle model. However, the YAK protocol is insecure as shown in References 7 and 20.…”

“…The known‐key security attackIt is expected that the EMSK produces unique common session keys. However, if a session key is revealed, this should not facilitate a passive attack to compromise future session key or an impersonation by an active attack 7,17 . In EMSK, suppose that the nine session keys (σ1 to σ9), see Figure 3, are known to an adversary.…”

“…It is designed under the perfect or unbreakable encryption assumption 37 which means that an attacker learns nothing from an encrypted message unless she/he knows the decryption key. Yang et al 7,38–43 used the Scyther tool for analyzing two complex group authentication protocols.…”

“…There are various algorithms which are based on public key encryption such as, Rivest, Shamir, Adliman (RSA), Diffie–Hellman key exchange (DH), elliptic curve Diffie–Hellman (ECDH), digital signature algorithm (DSA), elliptic curve digital signature algorithm (ECDSA), elliptic curve cryptography (ECC), ELGamal encryption algorithm, 3–5 YAK protocol 6 and improved YAK, 7 Menezes–Qu–Vanstone (MQV) protocol, and the hashed MQV (HMQV) protocol 8,9 …”