Questions tagged [cryptanalysis]
Cryptanalysis is the part of cryptology dedicated to the mathematical analysis of the weaknesses of cryptographic algorithms, the goal being to defeat some of the security properties that the algorithm should fulfill, e.g. decrypting data which has been symmetrically encrypted with substantially less effort than what would be needed to try out all possible keys.
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CrypTool - How to determine what type of encryption has been used?
I have a few questions about CrypTool.
How can you use the text analysis tools available in CrypTool to determine the encryption algorithm for a given ciphertext?
How can you use CrypTool's text ...
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Is specifying resume_offset for hybernation to LUKS-encrypted drive safe?
I need to enable hybernation to the LUKS-encrypted drive. My /boot partition is unencrypted hence it stores all kernel images as well as kernel parameters in unencrypted form. For hybernation to work ...
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How do RSA smartcards prevent key exfiltration?
Extracting private keys directly from the card is nearly impossible. With some acid package destruction and electron microscope work, a skilled team, and enough time, money, and luck you can in theory ...
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Vulnerabilities due to improper use of cipher's mode of operation? [closed]
I want to know if there was any vulnerability discovered - whether known to be exploited or not - in cryptographic systems due to improper use of the underlying block-based encryption algorithm's mode ...
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Attack against OTP Cipher [closed]
What would be an attack against an insecure instance of the OTP cipher given two challenge ciphertexts using the same key in order to get the plaintext? I've tried to implement some approaches with ...
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Can a Keypass file theoretically be cracked offline?
So you create a .kbdx file, protected by a password.
AFAIK in asymmetric key schemes and in WPA-AES brute-forcing consists of:
Trying a random password on the private key / on the router
If it doesn'...
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Storage of secret key in resource-constrained sensor nodes
In sensor nodes, there arises a need to store the master secret key safely. Which is the most perfect location to store the key when the sensor nodes (such as implanted body sensor node) are highly ...
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Using Chacha20 with a NULL nonce
I am new to ChaCha20. From the RFC --
The inputs to ChaCha20 are:
o A 256-bit key, treated as a concatenation of eight 32-bit little-
endian integers.
o A 96-bit nonce, treated as a ...
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How to calculate the redundancy of a language [closed]
I'm trying to calculating the unicity distance for a cipher applied to a language I wrote and I'm having trouble understanding the concept of redundancy in a language.
From this book
The ...
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How can I validate that a PRNG's output is insecure and predictable?
Say I talk to a developer who is using some output of a Pseudo-random number generator in order to do some security task. I know based upon common knowledge that only Cryptographically Secure Pseudo ...
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Does it weaken the encryption of SSH to use compression?
When using compression on openssh (a la ssh -C ...), does this reduce entropy and make the tunnel traffic more vulnerable to cryptanalysis? Is compression an option I should disable server-side for ...
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determine type of encoding/encryption [duplicate]
Is there a way to find out what type of encryption is being used on this data? I was playing around with a game data and i cant get around it .
This Is the data im trying to decrypt, any help?
Code:
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Find seed used in Math.random LCG given a list of outputs [duplicate]
Given one or two sequential Math.random outputs generated with Internet Explorer's linear congruential generator, is it possible to find the seed used in the LCG and find subsequent outputs? Here is ...
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Deciphering ciphertext with an unknown key and algorithm [closed]
How can I get started on understanding how to decipher this ciphertext when I don't know the algorithm or key used?
TDcbY xqCa NeAA OsWMirK FNFOm bYRUYAkxl, tqwl axZU XTaLrBSFv OI G vWjBZyqhz.
...
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Will prepending random data (of random length) result in more secure communication?
Many files begin with a "well-known" header sequence which I imagine helps a lot in performing cryptanalysis over a huge number of data transfers.
So I have the thought of prepending a block or two ...
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