Questions tagged [deniable-encryption]
Deniable encryption is a type of cryptography that allows an encrypted text to be decrypted in two or more ways, depending on which decryption key is used.
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Drawbacks of Deniable Encryption
What are the drawbacks of an encryption scheme being a deniable encryption scheme? Is there a generalized approach to convert an encryption scheme $\pi$ to $\pi'$ which will be a deniable encryption ...
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Can direct sums be used for deniable encryption?
So I've recently become acquainted with deniable encryption and I got to thinking, wouldn't a way to do this involve using a group that can be decomposed into direct summands which already have well-...
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Can a nonce be used to steganographically hide a message?
If a standard encryption scheme involves a nonce, as most do, can the nonce be used to hide another small message?
That is, the nonce (rather than being randomly generated) is a hidden message XORed ...
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Making a cipher non-malleable using a plaintext transform?
NOTE: By malleable/non-malleable, I mean the ability/or not to change a byte/block of the ciphertext and have it change only that byte/block of the plaintext.
I understand that we use authentication (...
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Is there any encryption system where the sender cannot prove that a specific ciphertext belongs to a specific plaintext
I'm trying to create a message-transfer system where
The encrypted messages are stored in a public database.
It is possible to verify who is the sender of this message.
The sender cannot prove to ...
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Symmetric Encryption in the P=NP world [duplicate]
I expected to find answers along the lines of quantum-computing insight into attacking AES; however, answers on this question aren't applicable because "Quantum computers give a quadratic speedup on a ...
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Does libsodium sealed box leak key ids?
I am using python and libnacl, which is a libsodium wrapper, to develop an application where users can deposit encrypted data.
Alice uses ...
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Is my deniable encryption scheme reasonable?
I was experimenting with RubberhoseFS, but since it is very hard to compile on anything modern, I decided to implement my own version, stripped of many unnecessary features. Namely, my implementation ...
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Please help a complete noob with deniable encryption! [duplicate]
I am completely new to cryptography and am interested in encrypting two basic text strings into one encrypted text that can be accessed separately with two different keys (preferably using something ...
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Perfect Deniability of a MAC
Overview
One feature that is often underlooked of the One-Time Pad is its perfect deniability. i.e. If Alice sends a message to Bob that is seen by Eve then if Eve later goes to Alice with the ...
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Deniability and Prekey Security in X3DH Key Agreement Protocol
Can someone please explain the below paragraphs from The X3DH Key Agreement Protocol?
1st paragraph: What is deniability and how does it work here?
Deniability
X3DH doesn't give either Alice ...
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Is LUKS Anti-Forensic information splitter (AFsplit) indistinguishable from random data?
I want to know if AFsplit(random_data_input, stripes, digestmod=sha) output is indistinguishable from random data.
The attacker ...
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Ciphers providing Deniable encryption?
I stumbled on the concept of Deniable encryption on Wikipedia, with the following scenario:
Deniable encryption allows the sender of an encrypted message to deny
sending that message. This ...
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Encryption with two meanings without computer or programming
Can one create a cipher with two meanings? Not two layers, two phrases in the same cipher in the way that it would have a meaning X, for example, if deciphered using Transposition cipher and meaning Y ...
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Non-deniability of data sent over TLS
Andy is going to connect to a server Selma over TLS. Later, Andy would like to be able to publish everything (the ciphertexts, the plaintexts, all his keys) and prove to a mediator what data he sent ...
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Concepts for realization in applied cryptography [closed]
I'm a computer science student (not a mathematican) and I'm gonna to write a master degree diploma on applied cryptography. Specifically, I'd like to create a realization of some cryptographic stuff ...
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Algorithm accepting every passphrase to fool unlegit user [closed]
I'm looking for specific names and literature on crypto algorithms that accept every passphrase input by the user, in order to 'decrypt' - even with false passphrase - and present the unlegit user ...
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Need to generate new DH keys for every message in OTR
Going through the OTR specification I don't quite get why a new DH keys (and hence new symmetric key and hmac key) are generated for each message to be sent. Why is this necessary? I don't think it ...
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Authentication and deniability
I have the following problem: Alice wants to send Bob a message such that Bob knows it is from Alice but at the same time he cannot prove that Alice send him this message.
The solution I came up with,...
user11693
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A specific way for deniable encryption
I read the summary of deniable encryption on wikipedia:
https://en.wikipedia.org/wiki/Deniable_encryption
Then I read a question, by doom123 on security.SE:
https:/...
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Implement deniable encryption with AES/RSA
I'm on a crypto app using OpenSSL (I'm more an implementer/cryptographer than a cryptologist), mainly as a hobby, for now.
My app will be able to encrypt a file (not a container) with symmetric or ...
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Is there an encryption/decryption algorithm that can give two different outputs?
The recent revelations that airport staff can detain travellers in an interrogation room and force them to give over passwords to encrypted-HDD laptops under threat of jail time has made me think ...
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Is there a way to encrypt multiple sets of data into one result, with separate keys decrypting each set of data
What I am picturing is something like this:
Block A: "Hello, how are you today?"
Block B: "The weather reminds me of summer."
I encode this, giving me two keys and a resulting encrypted block e.g.
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How to communicate by email with forward secrecy and deniability?
My correspondents and I would like to communicate privately by email. We used to employ PGP but that might have been shooting ourselves in the foot. PGP doesn't have forward secrecy. If any of our ...
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Deniability of OTR messaging
I've been looking at the off-the-record messaging protocol, and there is something about its deniability property that seems strange to me.
Consider the following scenario:
In the course of an OTR ...
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Untraceable communication protocol
I am doing a research about secure communication protocols.
I would be interested to know whether a protocol exists such that it grants that the two end-points taking part to the communication cannot ...
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Security of stream cipher based on Matrix multiplication GF(256) with randomized padding
The actual question is stated at the end of the text. Suppose you have a (grossly inefficient) confidentiality stream cipher with the following components:
The keyed function $F_k:\{0,1\}^{8n}\mapsto\...
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Encryption algorithm that produces dummy output on incorrect passwords
Background:
I've been thinking about using encryption in the context of backing up files to untrusted locations (to the point of making the file publicly and widely distributed for practically ...
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Anonymous trust/reputation system
Suppose there are 3 persons, Alice, Bob and Peter.
They are identified by their pseudonyms (public RSA keys).
Alice has a key Alice, Bob has ...
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Deniable Encryption from simple primitives
Is there a deniable encryption scheme $M = E(p_1,k_1,p_2,k_2,...,p_n,k_n), p_j = D(M,k_j)$ of $n$ plaintexts $p_1,p_2,...,p_n$ and $n$ keys $k_1,k_2,...,k_n$, such that we can fix $D$ to be a known ...
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