11 results sorted by ID
A Not So Discrete Sampler: Power Analysis Attacks on HAWK signature scheme
Morgane Guerreau, Mélissa Rossi
Attacks and cryptanalysis
HAWK is a lattice-based signature scheme candidate to the fourth call of the NIST's Post-Quantum standardization campaign. Considered as a cousin of Falcon (one of the future NIST post-quantum standards) one can wonder whether HAWK shares the same drawbacks as Falcon in terms of side-channel attacks. Indeed, Falcon signature algorithm and particularly its Gaussian sampler, has shown to be highly vulnerable to power-analysis attacks. Besides, efficiently protecting Falcon's signature...
Composing Timed Cryptographic Protocols: Foundations and Applications
Karim Eldefrawy, Benjamin Terner, Moti Yung
Foundations
Time-lock puzzles are unique cryptographic primitives that use computational complexity to keep information secret for some period of time, after which security expires. Unfortunately, current analysis techniques of time-lock primitives provide no sound mechanism to build multi-party cryptographic protocols which use expiring security as a building block. We explain in this paper that all other attempts at this subtle problem lack either composability, a fully consistent analysis, or...
Standard Model Time-Lock Puzzles: Defining Security and Constructing via Composition
Karim Eldefrawy, Sashidhar Jakkamsetti, Ben Terner, Moti Yung
Foundations
The introduction of time-lock puzzles initiated the study of publicly “sending information into the future.” For time-lock puzzles, the underlying security-enabling mechanism is the computational complexity of the operations needed to solve the puzzle, which must be tunable to reveal the solution after a predetermined time, and not before that time. Time-lock puzzles are typically constructed via a commitment to a secret, paired with a reveal algorithm that sequentially iterates a basic...
Resolving the Doubts: On the Construction and Use of ResNets for Side-channel Analysis
Sengim Karayalcin, Stjepan Picek
Attacks and cryptanalysis
The deep learning-based side-channel analysis gave some of the most prominent side-channel attacks against protected targets in the past few years.
To this end, the research community's focus has been on creating 1) powerful and 2) (if possible) minimal multilayer perceptron or convolutional neural network architectures. Currently, we see that computationally intensive hyperparameter tuning methods (e.g., Bayesian optimization or reinforcement learning) provide the best results. However,...
Improving Differential-Neural Cryptanalysis
Liu Zhang, Zilong Wang, Baocang wang
Attacks and cryptanalysis
In CRYPTO'19, Gohr introduced a novel cryptanalysis method by developing a differential-neural distinguisher using neural networks as the underlying distinguisher. He effectively integrated this distinguisher with classical differentials, facilitating a 12-round key recovery attack on Speck32/64 (from a total of 22 rounds). Bao et al. refined the concept of neutral bits, enabling key recovery attacks up to 13 rounds for Speck32/64 and 16 rounds (from a total of 32) for Simon32/64.
Our...
Cryptanalysis of Round-Reduced SIMON32 Based on Deep Learning
Zezhou Hou, Jiongjiong Ren, Shaozhen Chen
Deep learning has played an important role in many fields. It shows significant
potential to cryptanalysis. Differential cryptanalysis is an important method in
the field of block cipher cryptanalysis. The key point of differential cryptanalysis
is to find a differential distinguisher with longer rounds or higher probability.
Firstly, we describe how to construct the ciphertext pairs required for differential
cryptanalysis based on deep learning. Based on this, we train 9-round and...
Machine Learning Assisted Differential Distinguishers For Lightweight Ciphers (Extended Version)
Anubhab Baksi, Jakub Breier, Yi Chen, Xiaoyang Dong
Secret-key cryptography
At CRYPTO 2019, Gohr first introduces the deep learning based cryptanalysis on round-reduced SPECK. Using a deep residual network, Gohr trains several neural network based distinguishers on 8-round SPECK-32/64. The analysis follows an `all-in-one' differential cryptanalysis approach, which considers all the output differences effect under the same input difference.
Usually, the all-in-one differential cryptanalysis is more effective compared to the one using only one single differential...
Non-Interactive MPC with Trusted Hardware Secure Against Residual Function Attacks
Ryan Karl, Timothy Burchfield, Jonathan Takeshita, Taeho Jung
Cryptographic protocols
Secure multiparty computation (MPC) has been repeatedly optimized, and protocols with two communication rounds and strong security guarantees have been achieved. While progress has been made constructing non-interactive protocols with just one-round of online communication (i.e., non-interactive MPC or NI-MPC), since correct evaluation must be guaranteed with only one round, these protocols are by their nature vulnerable to the residual function attack in the standard model. This is...
Non-Interactive Multiparty Computation without Correlated Randomness
Shai Halevi, Yuval Ishai, Abhishek Jain, Ilan Komargodski, Amit Sahai, Eylon Yogev
We study the problem of non-interactive multiparty computation (NI-MPC) where a group of completely asynchronous parties can evaluate a function over their joint inputs by sending a single message to an evaluator who computes the output. Previously, the only general solutions to this problem that resisted collusions between the evaluator and a set of parties were based on multi-input functional encryption and required the use of complex correlated randomness setup.
In this work, we present...
On the Communication Complexity of Secure Computation
Deepesh Data, Manoj M. Prabhakaran, Vinod M. Prabhakaran
Foundations
Information theoretically secure multi-party computation (MPC) is a central
primitive of modern cryptography. However, relatively little
is known about the communication complexity of this primitive.
In this work, we develop powerful information theoretic tools to prove lower
bounds on the communication complexity of MPC. We restrict ourselves to a
concrete setting involving 3-parties, in order to bring out the power of
these tools without introducing too many complications. Our...
FlipIt: The Game of "Stealthy Takeover"
Marten van Dijk, Ari Juels, Alina Oprea, Ronald L. Rivest
Foundations
Recent targeted attacks have increased significantly in sophistication, undermining the fundamental assumptions on which most cryptographic primitives rely for security. For instance, attackers launching an Advanced Persistent Threat (APT) can steal full cryptographic keys, violating the very secrecy of "secret" keys that cryptographers assume in designing secure protocols. In this article, we introduce a game-theoretic framework for modeling various computer
security scenarios prevalent...
HAWK is a lattice-based signature scheme candidate to the fourth call of the NIST's Post-Quantum standardization campaign. Considered as a cousin of Falcon (one of the future NIST post-quantum standards) one can wonder whether HAWK shares the same drawbacks as Falcon in terms of side-channel attacks. Indeed, Falcon signature algorithm and particularly its Gaussian sampler, has shown to be highly vulnerable to power-analysis attacks. Besides, efficiently protecting Falcon's signature...
Time-lock puzzles are unique cryptographic primitives that use computational complexity to keep information secret for some period of time, after which security expires. Unfortunately, current analysis techniques of time-lock primitives provide no sound mechanism to build multi-party cryptographic protocols which use expiring security as a building block. We explain in this paper that all other attempts at this subtle problem lack either composability, a fully consistent analysis, or...
The introduction of time-lock puzzles initiated the study of publicly “sending information into the future.” For time-lock puzzles, the underlying security-enabling mechanism is the computational complexity of the operations needed to solve the puzzle, which must be tunable to reveal the solution after a predetermined time, and not before that time. Time-lock puzzles are typically constructed via a commitment to a secret, paired with a reveal algorithm that sequentially iterates a basic...
The deep learning-based side-channel analysis gave some of the most prominent side-channel attacks against protected targets in the past few years. To this end, the research community's focus has been on creating 1) powerful and 2) (if possible) minimal multilayer perceptron or convolutional neural network architectures. Currently, we see that computationally intensive hyperparameter tuning methods (e.g., Bayesian optimization or reinforcement learning) provide the best results. However,...
In CRYPTO'19, Gohr introduced a novel cryptanalysis method by developing a differential-neural distinguisher using neural networks as the underlying distinguisher. He effectively integrated this distinguisher with classical differentials, facilitating a 12-round key recovery attack on Speck32/64 (from a total of 22 rounds). Bao et al. refined the concept of neutral bits, enabling key recovery attacks up to 13 rounds for Speck32/64 and 16 rounds (from a total of 32) for Simon32/64. Our...
Deep learning has played an important role in many fields. It shows significant potential to cryptanalysis. Differential cryptanalysis is an important method in the field of block cipher cryptanalysis. The key point of differential cryptanalysis is to find a differential distinguisher with longer rounds or higher probability. Firstly, we describe how to construct the ciphertext pairs required for differential cryptanalysis based on deep learning. Based on this, we train 9-round and...
At CRYPTO 2019, Gohr first introduces the deep learning based cryptanalysis on round-reduced SPECK. Using a deep residual network, Gohr trains several neural network based distinguishers on 8-round SPECK-32/64. The analysis follows an `all-in-one' differential cryptanalysis approach, which considers all the output differences effect under the same input difference. Usually, the all-in-one differential cryptanalysis is more effective compared to the one using only one single differential...
Secure multiparty computation (MPC) has been repeatedly optimized, and protocols with two communication rounds and strong security guarantees have been achieved. While progress has been made constructing non-interactive protocols with just one-round of online communication (i.e., non-interactive MPC or NI-MPC), since correct evaluation must be guaranteed with only one round, these protocols are by their nature vulnerable to the residual function attack in the standard model. This is...
We study the problem of non-interactive multiparty computation (NI-MPC) where a group of completely asynchronous parties can evaluate a function over their joint inputs by sending a single message to an evaluator who computes the output. Previously, the only general solutions to this problem that resisted collusions between the evaluator and a set of parties were based on multi-input functional encryption and required the use of complex correlated randomness setup. In this work, we present...
Information theoretically secure multi-party computation (MPC) is a central primitive of modern cryptography. However, relatively little is known about the communication complexity of this primitive. In this work, we develop powerful information theoretic tools to prove lower bounds on the communication complexity of MPC. We restrict ourselves to a concrete setting involving 3-parties, in order to bring out the power of these tools without introducing too many complications. Our...
Recent targeted attacks have increased significantly in sophistication, undermining the fundamental assumptions on which most cryptographic primitives rely for security. For instance, attackers launching an Advanced Persistent Threat (APT) can steal full cryptographic keys, violating the very secrecy of "secret" keys that cryptographers assume in designing secure protocols. In this article, we introduce a game-theoretic framework for modeling various computer security scenarios prevalent...