Encrypted key exchange: password-based protocols secure against dictionary attacks
04 May 1992-pp 72-84
TL;DR: A combination of asymmetric (public-key) and symmetric (secret- key) cryptography that allow two parties sharing a common password to exchange confidential and authenticated information over an insecure network is introduced.
Abstract: Classic cryptographic protocols based on user-chosen keys allow an attacker to mount password-guessing attacks. A combination of asymmetric (public-key) and symmetric (secret-key) cryptography that allow two parties sharing a common password to exchange confidential and authenticated information over an insecure network is introduced. In particular, a protocol relying on the counter-intuitive motion of using a secret key to encrypt a public key is presented. Such protocols are secure against active attacks, and have the property that the password is protected against offline dictionary attacks. >
Citations
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25 Mar 2019
TL;DR: The main contribution of this paper is to raise awareness among wallet developers about the need to protect local RPC channels with the same prudence as network connections and it is hoped that it will discourage users to run security-critical applications like cryptocurrency wallets on shared systems or computers with guest account enabled.
Abstract: Many cryptocurrency wallet applications on desktop provide an open remote procedure call (RPC) interface that other blockchain-based applications can use to access their functionality. This paper studies the security of the RPC interface in several cryptocurrency wallets. We find that, in many cases, a malicious process running on the computer regardless of its privileges can impersonate the communication endpoints of the RPC channel and, effectively, steal the funds in the wallet. The attacks are closely related to server and client impersonation on computer networks but occur inside the computer. The malicious process may be created by another authenticated but unprivileged user on the same computer or even by the guest user. The main contribution of this paper is to raise awareness among wallet developers about the need to protect local RPC channels with the same prudence as network connections. We also hope that it will discourage users to run security-critical applications like cryptocurrency wallets on shared systems or computers with guest account enabled.
7 citations
TL;DR: FastZIP as discussed by the authors is a zero-interaction pairing scheme that uses fuzzy password-authenticated key exchange (fPAKE) protocol and utilizes sensor fusion to reduce the packet exchange time.
Abstract: With the advent of the Internet of Things (IoT), establishing a secure channel between smart devices becomes crucial. Recent research proposes zero-interaction pairing (ZIP), which enables pairing without user assistance by utilizing devices' physical context (e.g., ambient audio) to obtain a shared secret key. The state-of-the-art ZIP schemes suffer from three limitations: (1) prolonged pairing time (i.e., minutes or hours), (2) vulnerability to brute-force offline attacks on a shared key, and (3) susceptibility to attacks caused by predictable context (e.g., replay attack) because they rely on limited entropy of physical context to protect a shared key. We address these limitations, proposing FastZIP, a novel ZIP scheme that significantly reduces pairing time while preventing offline and predictable context attacks. In particular, we adapt a recently introduced Fuzzy Password-Authenticated Key Exchange (fPAKE) protocol and utilize sensor fusion, maximizing their advantages. We instantiate FastZIP for intra-car device pairing to demonstrate its feasibility and show how the design of FastZIP can be adapted to other ZIP use cases. We implement FastZIP and evaluate it by driving four cars for a total of 800 km. We achieve up to three times shorter pairing time compared to the state-of-the-art ZIP schemes while assuring robust security with adversarial error rates below 0.5%.
7 citations
27 May 2011
TL;DR: An improved two-party PAKE protocol is proposed which can provide several security attributes while it has a remarkable computational efficiency and lower number of rounds.
Abstract: Password Authenticated Key Exchange (PAKE) protocols enable two entities to agree on a common session key based on a pre-shared human memorable password. The main security goal of these protocols is providing security against password guessing attacks. In 2003, Hitchcock et al.'s protocol is presented. In 2005, Abdalla and Pointcheval proposed SPAKE1 and SPAKE2 protocols. In this paper, it is shown that the Hitchcock et al.'s protocol is vulnerable to ephemeral key compromise impersonation, off-line dictionary and Key Compromise Impersonation (KCI) attacks while it does not satisfy the mutual authentication and forward secrecy attributes. It is also shown that SPAKE1 and SPAKE2 protocols are vulnerable to password compromise impersonation and Denial-of-Service (DoS) attacks while they do not provide the mutual authentication property. To eliminate these weaknesses, an improved two-party PAKE protocol is proposed which can provide several security attributes while it has a remarkable computational efficiency and lower number of rounds.
7 citations
15 Nov 2011
TL;DR: A potential vulnerability in the password-based pairing protocol of the latest Bluetooth v4.0 proposed in 2010 is discovered, which makes password guessing possible and makes it a suitable replacement for the new Bluetooth pairing protocol.
Abstract: Bluetooth is a popular wireless communication technique, providing connection between portable or stationary devices in close range. A procedure called pairing needs to be performed when two devices intend to connect with each other in order to form a trusted pair and generate secret keys to protect the link. There are several modes of Bluetooth pairing, and password-based is the most convenient and prevalent way. In this paper, we discover a potential vulnerability in the password-based pairing protocol of the latest Bluetooth v4.0 proposed in 2010, which makes password guessing possible. To cope with the problem, a new scheme is proposed which can mitigate the network threats, and is compatible with the hardware of legacy Bluetooth devices. Note that our modification does not affect Bluetooth users' custom. This makes it a suitable replacement for the new Bluetooth pairing protocol.
7 citations
Patent•
22 Sep 2005
TL;DR: In this article, an authentication process and system for a wireless communication system between a host device and a client device is presented. And the authentication process can make the confirmation of the authentication easier and clearer.
Abstract: The present application relates to an authentication process and system for a wireless communication system between a host device and a client device. This authentication process and system can make the confirmation of the authentication easier and clearer.
7 citations
References
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TL;DR: This paper suggests ways to solve currently open problems in cryptography, and discusses how the theories of communication and computation are beginning to provide the tools to solve cryptographic problems of long standing.
Abstract: Two kinds of contemporary developments in cryptography are examined. Widening applications of teleprocessing have given rise to a need for new types of cryptographic systems, which minimize the need for secure key distribution channels and supply the equivalent of a written signature. This paper suggests ways to solve these currently open problems. It also discusses how the theories of communication and computation are beginning to provide the tools to solve cryptographic problems of long standing.
14,980 citations
"Encrypted key exchange: password-ba..." refers background or methods in this paper
...ElGamal’s algorithm is derived from the DiffieHellman exponential key exchange protocol[2]; accordingly, we will review the latter first....
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...And even this risk is minimal if B performs certain checks to guard against easily-solvable choices: that β is indeed prime, that it is large enough (and hence not susceptible to precalculation of tables), that β − 1 have at least one large prime factor (to guard against Pohlig and Hellman’s algorithm[13]), and that α is a primitive root of GF (β)....
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...The use given above for asymmetric encryption — simply using it to pass a key for a symmetric encryption system — is an example of what Diffie and Hellman[2] call a public key distribution system....
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...It works especially well with exponential key exchange [2]....
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TL;DR: An encryption method is presented with the novel property that publicly revealing an encryption key does not thereby reveal the corresponding decryption key.
Abstract: An encryption method is presented with the novel property that publicly revealing an encryption key does not thereby reveal the corresponding decryption key. This has two important consequences: (1) Couriers or other secure means are not needed to transmit keys, since a message can be enciphered using an encryption key publicly revealed by the intented recipient. Only he can decipher the message, since only he knows the corresponding decryption key. (2) A message can be “signed” using a privately held decryption key. Anyone can verify this signature using the corresponding publicly revealed encryption key. Signatures cannot be forged, and a signer cannot later deny the validity of his signature. This has obvious applications in “electronic mail” and “electronic funds transfer” systems. A message is encrypted by representing it as a number M, raising M to a publicly specified power e, and then taking the remainder when the result is divided by the publicly specified product, n, of two large secret primer numbers p and q. Decryption is similar; only a different, secret, power d is used, where e * d ≡ 1(mod (p - 1) * (q - 1)). The security of the system rests in part on the difficulty of factoring the published divisor, n.
14,659 citations
"Encrypted key exchange: password-ba..." refers methods in this paper
...Section 2 describes the asymmetric cryptosystem variant and implementations using RSA[ 3 ] and ElGamal[4]....
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...We will use RSA[ 3 ] to illustrate the difficulties....
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23 Aug 1985
TL;DR: A new signature scheme is proposed, together with an implementation of the Diffie-Hellman key distribution scheme that achieves a public key cryptosystem that relies on the difficulty of computing discrete logarithms over finite fields.
Abstract: A new signature scheme is proposed, together with an implementation of the Diffie-Hellman key distribution scheme that achieves a public key cryptosystem. The security of both systems relies on the difficulty of computing discrete logarithms over finite fields.
7,514 citations
19 Aug 1984
TL;DR: In this article, a new signature scheme is proposed together with an implementation of the Diffie-Hellman key distribution scheme that achieves a public key cryptosystem and the security of both systems relies on the difficulty of computing discrete logarithms over finite fields.
Abstract: A new signature scheme is proposed together with an implementation of the Diffie - Hellman key distribution scheme that achieves a public key cryptosystem. The security of both systems relies on the difficulty of computing discrete logarithms over finite fields.
2,351 citations
Book•
01 Jan 1982TL;DR: The goal of this book is to introduce the mathematical principles of data security and to show how these principles apply to operating systems, database systems, and computer networks.
Abstract: From the Preface (See Front Matter for full Preface)
Electronic computers have evolved from exiguous experimental enterprises in the 1940s to prolific practical data processing systems in the 1980s. As we have come to rely on these systems to process and store data, we have also come to wonder about their ability to protect valuable data.
Data security is the science and study of methods of protecting data in computer and communication systems from unauthorized disclosure and modification. The goal of this book is to introduce the mathematical principles of data security and to show how these principles apply to operating systems, database systems, and computer networks. The book is for students and professionals seeking an introduction to these principles. There are many references for those who would like to study specific topics further.
Data security has evolved rapidly since 1975. We have seen exciting developments in cryptography: public-key encryption, digital signatures, the Data Encryption Standard (DES), key safeguarding schemes, and key distribution protocols. We have developed techniques for verifying that programs do not leak confidential data, or transmit classified data to users with lower security clearances. We have found new controls for protecting data in statistical databases--and new methods of attacking these databases. We have come to a better understanding of the theoretical and practical limitations to security.
1,937 citations
"Encrypted key exchange: password-ba..." refers background in this paper
...Can such a random odd number less than a known n be distinguished from a valid public key e? Assume that p and q are chosen to be of the form 2p′ + 1 and 2q′ + 1, where p′ and q′ are primes, a choice that is recommended for other reasons [9]....
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