302 views

### If you have a file and XOR every bit with a random bit, can you extract any information?

Say you have a file that is not random, and you XOR every bit with a random bit (not pseudo, but really random). Can someone who sees only the result extract any information from it? Obviously, it won'...
167 views

### One-time pad encryption - how does the receiving side decrypt the message?

If a message is sent using one-time pad scheme, which generates random bits in order to, for example, XOR them with the message's bits - how does the receiving side generate the exact series of bits ? ...
167 views

### Krack WPA2 decrypt only some small pieces of packets

I have gone through the paper (PDF) available at krackattacks.com. However, from what I understood you force a key reinstallation causing you a nonce reuse over 2 blob of data. As it is a keystream, ...
266 views

### How to compromise the privacy of NaCl encrypted messages, when nonce is reused?

I want to know to how break NaCl encryption when a nonce is used more than once for a given key private key. According to PyNaCl docs: It is VITALLY important that the nonce is a nonce, i.e. it is ...
139 views

### Why don't most encryption algorithms use perfect secrecy?

Isn't it possible to make algorithms that are both computationally complex and have many possible answers if you try to crack them without knowing the password? Why aren't many popular algorithms like ...
374 views

### Comparing DES and DES-X variation: $Enc(m) = DES_{k_1}(m \oplus k_2)$

I came across this question: Test the security of the following variation of DES-X cryptosystem, which uses 2 keys $k_1$ and $k_2$: $$Enc(m) = DES_{k_1}(m \oplus k_2)$$ (Basically, it uses the 2nd ...
249 views

### Decrypt a message which is encrypted using XOR? [duplicate]

This is a puzzle asked in a contest. Given that encryption , decryption happens as per following rule/code: ...
100 views

### Sweet32: Can a single 8 byte block session ID be exploited by this vulnerability?

Im currently developing a authentication scheme. The authentication scheme will use a 64 bit encryption to encrypt its session ID. Here is how the authentication system will work: For each session, ...
93 views

### Attacks on one-time pad, given a property of keys

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 \$...
92 views

### Is there any vulnerability in this scheme?

We want to design a symmetric encryption scheme. Note that the following things are true for our system: The plaintext P will change every time for a given user. A user will choose a password which ...