Questions tagged [decryption]

In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Only authorized parties can decipher a ciphertext back to plaintext and access the original information.

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Tonelli-Shank vales are incorrect when trying to get back to c value for Rabin [duplicate]

I'm working (banging head against wall) on a Rabin encryption as part of a challenge. I thought I was making progress as several algorithms had given em the same values for the mod sqrt but it seems ...
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How to decrypt Rabin message when p=q and you have the roots from Tonelli-Shanks

I've been trying to decrypt a message encrypted with Rabin as a challenge. I'm very new to cryptography and these challenges so much of this is new. I've factorised n and determined that p=q which I ...
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How to calculate time needed for decryption of 64-bit key

I am having trouble figuring out how long it takes to decrypt a 64-bit key, given that a computer can do 1 billion trials per second. I know that there are $2^{64} = 1.844 \times 10^{19}$ possible ...
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Encryption and decryption of Request and response for REST API

I am working on encryption/decryption for the rest of the API. The client here can be mobile, desktop, web browsers, etc and all the requests will be made to an https endpoint. The main goal here is ...
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How to encrypt a string and decrypt a string but public can never figure out how to encrypt/decrypt a string

On my website I display an image. To generate this image, it require a string parameters. For example the string 1234,2423,1231 as the parameter. Anyone can use my ...
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Identify the value of the plaintext from a noised expression

Having the following instructions: Using Paillier encryption to encrypt $m$. So, we get $Enc(m)$ Multiply $Enc(m)$ and $A$ to Get $C$. So, $C = Enc(m).A$ Decrypt $C$ using Paillier Decryption ...
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Forgery attack on Poly1305 when the key and nonce reused

Introduction: I've tried to find how reusing one-time key compromises itself but only found information that it breaks the encryption entirely, it is written everywhere. But since no methods to reuse ...
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Will Fernet’s key function at any timeframe?

I’m very new to cryptography and I need to use a symmetric cryptography approach. My simple question is, will the key always at any time be able to decrypt the encrypted text? The encrypted text may ...
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Cryptography elements needed for a story

Note: following Maarten Bodewes's answer, I edited this post to make it clearer. I'm writing something partly driven by the need to crack a few encrypted files. This is what needs to happen in the ...
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Good layperson analogy for password and encryption keys

NOTE: QUESTION UPDATED. SEE BOTTOM OF THIS POST. I'm writing something where I need to make someone come across as though they know cryptography. I don't know enough, but as cryptography plays only a ...
156 views

How the message is decrypted in an RSA chosen ciphertext attack when it's a modulo?

During the last stage of decryption of a chosen ciphertext attack we are left off with this equation $$c = m \cdot t \pmod n$$ Removing all exponents like $d$ and $e$ where $c$ is the decrypted ...
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How RSA-OAEP decrypt a Symmetric Key message?

In an RSA-OAEP encrypted symmetric Key (AES for example) message. The message is then decrypted by the other party when R is a Random Number That other party doesn't know about. so How it can retrieve ...
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Zodiac unsolved 340 cipher decryption in 2020

This is a rather general question, but I'd really appreciate your (experts, in my view) opinion on this subject. I was wondering if, using current tech like machine learning, quantum computers and ...
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