Efficient Three Party Key Exchange Protocol

Key exchange protocols allow two or more parties communicating over a public network to establish a common secret key called a session key. In 1976, Diffie and Hellman proposed the first practical key exchange (DH key exchange) protocol. In 2005, Abdalla and Pointcheval suggested a new variation of the computational DH assumption called chosen based computational Diffie Hellman (CCDH) and presented simple password based authenticated key exchange protocols. Since then several three party password authenticated key agreement protocols have been proposed In 2007, Lu and Cao proposed a simple 3 party authenticated key exchange (S-3PAKE) protocol. Kim and Koi found that this protocol cannot resist undetectable online password guessing attack and gave fixed STPKE' protocol as a countermeasure using exclusive-or operation. Recently, Tallapally and Padmavathy found that STPKE' is still vulnerable to undetectable online password guessing attack and gave a modified STPKE' protocol. Unfortunately, we find that, although modified STPKE' protocol can resist undetectable online password guessing attack but it is vulnerable to man in the middle attack. Also, we propose and analyze an efficient protocol against all the known attacks

Analysis of two pairing-based three-party password authenticated key exchange protocols

Password-Authenticated Key Exchange (PAKE) protocols allow parties to share secret keys in an authentic manner based on an easily memorizable password. Recently, Nam et al. showed that a provably secure three-party password-based authenticated key exchange protocol using Weil pairing by Wen et al. is vulnerable to a man-in-the-middle attack. In doing so, Nam et al. showed the flaws in the proof of Wen et al. and described how to fix the problem so that their attack no longer works. In this paper, we show that both Wen et al. and Nam et al. variants fall to key compromise impersonation by any adversary. Our results underline the fact that although the provable security approach is necessary to designing PAKEs, gaps still exist between what can be proven and what are really secure in practice

Cryptanalysis of an e_cient three-party password-based key exchange scheme

AbstractIn order to secure communications between two clients with a trusted server's help in public network environments, a three-party password-based authenticated key exchange (3PAKE) scheme is used to provide the transaction confidentiality and e_ciency. In 2010, Lou-Huang proposed a new simple three-party password-based authenticated key exchange (LH-3PAKE) scheme based on elliptic curve cryptography (ECC). By analysis, Lou-Huang claimed that the proposed LH- 3PAKE scheme is not only secure against various attacks, but also more e_cient than previously proposed 3PAKE schemes. However, this paper demonstrates LH-3PAKE scheme is vulnerable to o_-line password guessing attacks by an attacker

CALIPER: Continuous Authentication Layered with Integrated PKI Encoding Recognition

Architectures relying on continuous authentication require a secure way to challenge the user's identity without trusting that the Continuous Authentication Subsystem (CAS) has not been compromised, i.e., that the response to the layer which manages service/application access is not fake. In this paper, we introduce the CALIPER protocol, in which a separate Continuous Access Verification Entity (CAVE) directly challenges the user's identity in a continuous authentication regime. Instead of simply returning authentication probabilities or confidence scores, CALIPER's CAS uses live hard and soft biometric samples from the user to extract a cryptographic private key embedded in a challenge posed by the CAVE. The CAS then uses this key to sign a response to the CAVE. CALIPER supports multiple modalities, key lengths, and security levels and can be applied in two scenarios: One where the CAS must authenticate its user to a CAVE running on a remote server (device-server) for access to remote application data, and another where the CAS must authenticate its user to a locally running trusted computing module (TCM) for access to local application data (device-TCM). We further demonstrate that CALIPER can leverage device hardware resources to enable privacy and security even when the device's kernel is compromised, and we show how this authentication protocol can even be expanded to obfuscate direct kernel object manipulation (DKOM) malwares.Comment: Accepted to CVPR 2016 Biometrics Worksho