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### many time pad attack [duplicate]

I am a beginner in cryptography. I studied many time pad attack and now I want to solve a popular exercise, It consists 11 ciphertexts (s1,s2,...,s11), that encrypted by a same key and I want to find ...
498 views

### One-time pad encryption of ASCII characters [duplicate]

I can't understand a question I came across in a course. You observe three ciphertexts all resulting from encryption of ASCII plaintexts containing English letters and spaces only, using the ...
68k views

### How does one attack a two-time pad (i.e. one time pad with key reuse)?

My question might appear the same as the question Taking advantage of one-time pad key reuse?, but actually I did read all the answers and none of them helped me with the details I need. I am new to ...
11k views

### Many time pad attack (XOR) [duplicate]

The question is quite similar to Many time pad attack and I was trying to rely on the top answer, but still am a bit confused, so any explanation and help will be much appreciated. Assume I have a ...
4k views

### Security of very simple XOR with random? [duplicate]

I am currently trying to implement a very fast and simple encryption algorithm in Lua for the purpose of using it with ComputerCraft. The main problem is that bitwise operations in Lua (5.2 at least) ...
6k views

### Cryptanalysis of XOR cipher with repeated key phrase

My assignment is to cryptanalyze cipher text that we know was encrypted with a stream cipher (bitwise XOR of plain text and key stream), and decrypt to plain text. We know the key stream is a repeated ...
4k views

### decryption many time pad [duplicate]

I have eleven ciphertexts that were encrypted with the same key (which I don't know). I want to decrypt the last ciphertext. I read similar question like Many time pad attack but I can't solve my ...
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### What does it mean when two encrypted files, encrypted with the same method but with different keys, when xor'd together, produce a repeating pattern?

Let's say I have fileA and fileB, both encrypted somehow, but in the same method with different keys. If I xor them together, they will make a repeating pattern of 32 bytes length. What does that say ...
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### What are the vulnerabilities of this OTP-like system?

I've read that a OTP is only perfectly secure if the key is perfectly random, and the pad is never reused. If you encrypt documents using two keys, where one is random but stays constant for some ...
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### Little problem with Vernam Cipher

We have got a task with the following content: Given is a language with 3 letters: A, B, C. The binary expression is: A = 000, B = 1111 and C = 0011 Two ...
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### Is it easier to crack the Vernam Cipher with more than two ciphertexts

I have just started looking into the cracking of the Vernam cipher with two ciphertexts encrypted with the same key by XORing them and then crib dragging and I was wondering if it is made easier if ...
An adversary $A$, eavesdrops $n$ cipher-texts, $c_{1}, c_{2} ..., c{_n}$. It also knows a value $v$ and a function $f$ such that $$f(k_{1}, k_{2}, ..., k_{n}) = v$$ where, $k_{i}$ is used to encrypt \$...