A cipher or mode of operation is said to be malleable if it is feasible to modify ciphertext to produce meaningful changes in the corresponding plaintext without knowing the encryption key.
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Why is Blum-Goldwasser not IND-CCA-2 secure?
Consider the Blum-Goldwasser encryption scheme as described on Wikipedia. I was told that it was not IND-CCA-2 secure.
I heard there was malleabilty, probably it has to do with XOR-ing. But I do not ...
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Is there any known malleability of scrypt outputs?
The scenario is single-use passphrase-based non-interactive message authentication.
The obvious try to do this is to chose a random salt of the appropriate length and send:
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Malleability attacks against encryption without authentication
Suppose there is a message that is encrypted with AES-128-CBC. The message is as follows, new lines are used to delimit the 16 byte boundary for each block:
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Stream cipher malleability
Considering a stream cipher that produces a ciphertext "c" from a message "m" and a key "k" is it possible to apply operations (multiplication and/or addition) directly to "c" without knowing the key ...
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Is there a way to break this encryption?
I was wondering about making up a simple system to encrypt a file:
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What type of hash functions provides non-malleability of hash digests?
I want to use a hash function for commitments. I don't want an attacker to construct a commitment related to a previously published (but still unopened) commitment.
A simple deterministic commitment ...
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Malleability of ElGamal and Hashed ElGamal
Question: Suppose A encrypts a number $x$ which indicates her bid on a contract, using ElGamal encryption. Say that the encryption of $x$ produces a ciphertext $c$. Explain how E can modify $c$ to ...
