Questions tagged [adversarial-model]
An adversary model formally defines the power of the adversary. It includes specifics whether the adversary is deterministic/randomized, uniform/non-uniform, interactive/non-interactive and how he interacts with the security game.
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Difference between non-collusion and single-party corruption assumptions
In the context of secure multi-party computation (MPC), I often see different assumptions about the adversary.
What is the difference between the non-colluding assumption and the assumption that the ...
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What is an adversary type?
The term "type 1 adversary" was used and I was curious as to what determines the adversarial type's category? Is it a well defined term within the cryptographic community? Please note that I'...
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What is the size of an adversary?
I was reading a SMPC paper, and it writes that "non-uniform adversary A of size $\text{poly}(λ)$".
What is the size of adversary in secure multiparty computation, and where can I find some ...
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PFS and PCS Game
Where can I find a formal security definition for Perfect Forward Secrecy (PFS) and Post-Compromise Security (PCS) that includes a cryptographic game model and a challenge-response structure, ...
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An upper bound for advantage related to differential privacy
My previous question define a security game, advantage $\mathsf{Adv}$ and two probability distributions $P_{m_0}$ and $P_{m_1}$, representing $Enc_k(m_0)$ and $Enc_k(m_1)$ separately.
There, my main ...
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An upper bound for advantage in a security game
Suppose I have defined a security game in a private-key (symmetric) encryption scheme.
Remark: Note that encryption algorithm is probabilistic, so for a specific message m, $Enc_k(m)$ might output a ...
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Understanding Adversary's Advantage for Target Key Recovery in Ideal Cipher Model
In the ideal cipher model, a block cipher is modeled by a different, independent random permutation for every key.
Let $$ \mathcal{A}_{q}^{\text{IC-EKS}} $$ be a ( q )-query exhaustive key-search ...
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Certificateless public key cryptography
In the Wikipedia article on Certificateless Public Key Cryptography https://en.wikipedia.org/wiki/Certificateless_cryptography, it states, "For tight security, a certificateless system has to ...
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Reduction from factoring to RSA and the Oracle RSA problem
Recently I read some papers related to RSA Brown16,AM09,BNPS01 and I learned that there is a variant problem of RSA is The oracle RSA problem (or one more RSA Problem) is $m+1$ copies of the classic ...
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Signature forgery in different adversarial settings
I'm currently studying the different adversarial settings for digital signatures.
In Goldwasser, Micali and Rivests paper they propose three different chosen message attack settings, which are vastly ...
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Replacing the Hash function with messages in the BLS signature scheme, the security degenerates from EUF to SUF?
I have been thinking about this question: if I directly replace the hash function with the message in the BLS signature, does the security of the BLS degenerate from existential unforgeability(EUF) to ...
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Confirming understanding of security protocol modelled in Scyther
In university, I'm currently learning how to use Scyther to model security protocols. Currently I am trying to understand what is happening in an example protocol given to me which is:
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Automated Security Protocol tool that models algebraic operations
Are there any automated security protocol verification tools that model algebraic operations; specifically addition.
I am familiar with AVISPA and Verifpal, and they are both great and user-friendly ...
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Breaking CDH also breaks DHI
I am trying to show that by breaking the Computational Diffie-Hellmann (CDH) assumption one also breaks the Diffie-Hellmann inverse assumption. Unfortunately, I am a bit stuck and do not know where to ...
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Why is a protocol that is secure in the presence of a malicious adversary also secure in the presence of an augmented semi-honest adversary？
Proposition Let π be a protocol that securely computes a functionality f in the presence of malicious adversaries. Then π securely computes f in the presence of augmented semi-honest adversaries.
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