instruction stringlengths 15 30k |
|---|
**Protocol:** Coin Flipping over telephone
**Hypothesis:**
Alice and Bob have agreed:
1. a one to one function $f$ which is easy to compute $f(x)$ from $x$ and while given any value $f(x)$ it is nearly impossible to find any information about $x$.
2. an even number $x$ in $f(x)$ represent HEAD and the other... |
Based on what mentioned in the paper "Pairings For Cryptographers"
http://www.sciencedirect.com/science/article/pii/S0166218X08000449
the two inputs of a pairing map are two members of two additive groups on elliptic curves, while the output is an element of a multiplicative group on a finite field.
![enter image d... |
**Protocol:** Coin Flipping over telephone
**Hypothesis:**
Alice and Bob have agreed:
1. a one to one function $f$ which is easy to compute $f(x)$ from $x$ and while given any value $f(x)$ it is nearly impossible to find any information about $x$.
2. an even number $x$ in $f(x)$ represent HEAD and the other... |
Given a (bad) modification of DSA where the has function is the identity ($H(m)=m$), I am now supposed to design an attack. So $(m, (r,s))$ are given and I should be able to create a legit signature $(r',s')$ for any $m'$.
I don't really know how $H(m)=m$ helps me. Apparantly, I'll have to calculate the private key ... |
I'm studying this white-paper: http://jessekornblum.com/publications/di09.pdf
The author says that using AES-CCM with the external key (highlighted in green at page 9, figure 4) and with the nonce at offset `0x3662B8` (highlighted in red, figure 5) you can decrypt the data at offset `0x3662D4`.
I don't understand... |
Given a (bad) modification of DSA where the hash function is the identity ($H(m)=m$), I am now supposed to design an attack. So $(m, (r,s))$ are given and I should be able to create a legit signature $(r',s')$ for any $m'$.
I don't really know how $H(m)=m$ helps me. Apparantly, I'll have to calculate the private key... |
Based on what mentioned in the paper "Pairings For Cryptographers"
http://www.sciencedirect.com/science/article/pii/S0166218X08000449
the two inputs of a pairing map are two members of two additive groups on elliptic curves, while the output is an element of a multiplicative group on a finite field.
![enter image d... |
The multiplier parameter $k$ [is different][1] between SRP 6 and 6a. You can see that RFC 5054 [calculates][2] it using a hash of the domain parameters (modulus $N$ and generator $g$), so it is using SRP 6a, as opposed to SRP 6 where $k$ is constant.
Likewise, in section 6.2.1 of IEC 11770-4 – the October 2005 draft... |
Given a (bad) modification of DSA where the hash function is the identity ($H(m)=m$), I am now supposed to design an attack. So $(m, (r,s))$ are given and I should be able to create a legit signature $(r',s')$ for a **chosen** $m'$ (of course $m'\neq m$).
I don't really know how $H(m)=m$ helps me. Apparantly, I'll h... |
My understanding are these steps are necessary for symmetric cryptography to be IND-CPA:<br>
1- The adversary submits two distinct M0, M1 plain-texts to the challenger<br>
2- The challenger selects one of them at random and encrypts it with the symmetric key and gives cipher-text C<br>
3- The adversary has to guess ... |
I'm doing Matasano's challenges and struggling with second part of 49th problem where I'm asked to do the length extension attack with CBC-MAC without IV manipulation. There is a hint that I can simulate iv somehow to do this but I don't understand. Can someone drop me some hint atleast? I did the part with forging the... |
My understanding are these steps are necessary for symmetric cryptography to be IND-CPA:
1. The adversary submits two distinct $M_0$, $M_1$ plain-texts to the challenger.
2. The challenger selects one of them at random and encrypts it with the symmetric key and gives cipher-text C.
3. The adversary has to guess wh... |
This may be a relatively easy question to answer, but I am not a cryptography expert. It is merely a hobby of mine.
Does there exist a cipher that can be encrypted twice with two different keys and then decrypted twice using either key first? For example:
Plaintext is "Lemons are great!"
Encode with Key ... |
How to calculate complexity of ElGamal cryptosystem? |
I'm implementing an entropy gathering program.
For that I collect 2 bits from two gpio-pins connected to a random source.
I whiten this stream of bits using the von Neumann decorrelation algorithm (see https://en.wikipedia.org/wiki/Hardware_random_number_generator#Software_whitening ). Now 2 out of 4 cases I can't ... |
collecting entropy: can I use timing of reading as a seperate source from the reading itself? |
I'm implementing an entropy gathering program.
For that I collect 2 bits from two gpio-pins connected to a random source.
I whiten this stream of bits using [the von Neumann decorrelation algorithm](https://en.wikipedia.org/wiki/Hardware_random_number_generator#Software_whitening). Now 2 out of 4 cases I can't use ... |
Collecting entropy: can I use timing of reading as a separate source from the reading itself? |
I plan on storing data, encrypted with AES256, where the first dozen bytes are known plaintext. ('Hello World!' for example.)
Does having this known plaintext prefix weaken AES256?
I do not care about modifications being made to the ciphertext, which result in modifications to the decrypted plaintext.
I do ca... |
Does having a known plaintext prefix weaken AES256? |
Given a (bad) modification of DSA where the hash function is the identity ($H(m)=m$), I am now supposed to design an attack. So $(m, (r,s))$ are given and I should be able to create a legit signature $(r',s')$ for a **chosen** $m'$ (of course $m'\neq m$).
Since retrieving the private key $x$ doesn't work. My new app... |
With my new idea I seem to solve the problem and answer my question, so I'll go ahead and post it as the answer. I choose the new $m'$ as $m'=t+m$ with $t>0$.
Now the verification works like this:
$v'=g^{m'w} A^{rw}=g^{m'w+arw}=g^{tw+mw+arw}=g^{tw} \cdot g^k=r' \mod q$
So my new $r'=g^{tw}r=g^{ts^{-1}}r$
This... |
What i know about the string:
- The algorithm is AES (Rijndael)
- Blocksize: 128
- Keysize: 256
- All bytes in the key has an integer value between 0 and 16.
- The initialization vector is (base64 encoded): "DkBbcmQo1QH+ed1wTyBynA=="
If so, how should i do it?
-- it's for a challenge |
Can i crack an AES string if i have all these parameters? |
What i know about the string:
- The algorithm is AES (Rijndael)
- Blocksize: 128
- Keysize: 256
- You only need to find the first 6 bytes of the key, the rest are 0’s, so:
[?,?,?,?,?,?,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
- All bytes in the key has an integer value between 0 and 16.
... |
With my new idea I seem to solve the problem and answer my question, so I'll go ahead and post it as the answer. I choose the new $m'$ as $m'=t+m$ with $t>0$.
Now the verification works like this:
$v'=g^{m'w} y^{rw}=g^{m'w+xrw}=g^{tw+mw+xrw}=g^{tw} \cdot g^k=r' \mod q$
So my new $r'=g^{tw}r=g^{ts^{-1}}r$
This... |
I am pretty new to cryptography and have a sample of GCM mode of operation for AES.
PFB the code
Cipher c = Cipher.getInstance ("AES/GCM/NoPadding");
final int blockSize = 96;//c.getBlockSize();
final byte[] ivData = new byte[blockSize];
System.out.println("IV :- "+new String(ivData) );
final Sec... |
What i know about the string:
- The algorithm is AES (Rijndael)
- Blocksize: 128
- Keysize: 256
- I only need to find the first 6 bytes of the key, the rest are 0’s, so:
`[?,?,?,?,?,?,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]`
- All bytes in the key has an integer value between 0 and 16.
... |
I have a cipher text which is encrypted using AES128 Algorithm.
I want to know the following things to decrypt the cipher.
- IV (Initialization Vector)
- Padding Method
- Encryption Key
How do I find the Padding method used in the encryption? |
How to find which padding method is used in Block cipher(AES) encyption? |
Firstly, How much time will it take to crack PBKDF2 while using a 9 character password? and how do I calculate the cost? I'm not specifying any specific system or platform. If a brute force attack is made using the best ever super computer around how much time will it take to crack it?
Secondly, Is PBKDF2 the best e... |
How long does it take to crack PBKDF2? |
How much time will it take to crack PBKDF2 while using a 9 character password? I'm not specifying any specific system or platform. If a brute force attack is made using the best ever super computer around how much time will it take to crack it?
|
> Firstly, How much time will it take to crack PBKDF2 while using a 9 character password? and how do I calculate the cost? I'm not specifying any specific system or platform. If a brute force attack is made using the best ever super computer around how much time will it take to crack it?
Unless the underlying PRF is... |
[Sakura][1] specifies a tree hash mode for e.g. Keccak (SHA-3). Are there any reasons to use the Sakura tree hash mode in a [Generalized Merkle Signature Scheme][2]? It seems to me Sakura primarily solves a uniqueness problem with using tree hashes for large data when the depth of the tree is variable. This problem doe... |
[Sakura][1] specifies a tree hash mode for e.g. Keccak (SHA-3). Are there any reasons to use the Sakura tree hash mode in a [Generalized Merkle Signature Scheme][2]? It seems to me Sakura primarily solves a uniqueness problem with using tree hashes for large data when the depth of the tree is variable.
Trivially, if... |
[PBKDF2][1] (as defined by [RFC 2898][2]) is a function of the form
$$DK = \text{PBKDF2}(\text{PRF}, Password, Salt, c, dkLen)$$
In most practical use cases, the [$\text{PRF}$][2] is [$\text{HMAC}$][3] instantiated with a [Merkle-Damgård][4] [hash][5] function such as [$\text{SHA-1}$][6]. The time to compute $\te... |
[PBKDF2][1] (as defined by [RFC 2898][2]) is a function of the form
$$DK = \text{PBKDF2}(\text{PRF}, Password, Salt, c, dkLen)$$
In most practical use cases, the [$\text{PRF}$][2] is [$\text{HMAC}$][3] instantiated with a [Merkle-Damgård][4] [hash][5] function such as [$\text{SHA-1}$][6]. The time to compute $\te... |
As in the title, given $g$, $b$ and $g^{ab}$ are big elements in a prime group $Z_p$. Is finding $g^a$ a hard problem? |
Given $g$, $b$, $g^{ab}$, is finding $g^a$ a hard problem? |
As in the title, given $g$, $g^{ab}$ are big elements in a prime group $Z_p$ and $b$ in group $Z_r$. $a$ is unknown and also in $Z_r$, is finding $g^a$ a hard problem? |
As in the title, given $g$, $g^{ab}$ are big elements in a prime group $Z_p$ and $b$ in prime group $Z_r$ ($p > r$, $g$ is one generator of $Z_p$). $a$ is unknown and also in $Z_r$, is finding $g^a$ a hard problem? |
[PBKDF2][1] (as defined by [RFC 2898][2]) is a function of the form
$$DK = \text{PBKDF2}(\text{PRF}, Password, Salt, c, dkLen)$$
In most practical use cases, the [$\text{PRF}$][3] is [$\text{HMAC}$][4] instantiated with a [Merkle-Damgård][5] [hash][6] function such as [$\text{SHA-1}$][7]. The time to compute $\te... |
If you can use something more lightweight than pairings then you should skip pairings. There is a technical property of pairings than is not the case with other crypto primitives. And this is the evaluation of multiplications on the exponent that cannot be achieved in other cases. If you need some sort of summation the... |
What I know about the string:
- The algorithm is AES (Rijndael)
- Blocksize: 128
- Keysize: 256
- I only need to find the first 6 bytes of the key, the rest are 0’s, so:
`[?,?,?,?,?,?,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]`
- All bytes in the key have an integer value between 0 and 16.
... |
Can I crack an AES string if I have all these parameters? |
I have been reading around (mostly various stackexchange sites, wiki and a few blogs/forum posts) about encryption and various techniques. I have read that doing a one time pad using XOR isn't secure unless the key is as long as the input, is sufficiently random, and not reused. They reference things such as the plain ... |
How secure is using a one time pad (using xor) on a encrypted data, for the purpose of obfuscating/hiding the underlying encryption? |
This is for [a challenge at followthewhiterabbit.trustpilot.com][1]:
> We have a message for you.
It’s 3ncryp73d and we want you to crack it.
The decrypted message will contain further instructions.
> Knowns:
> - The algorithm is AES (Rijndael)
- Blocksize: 128
- Keysize: 256
- You only need to find ... |
I have been reading around (mostly various stackexchange sites, wiki and a few blogs/forum posts) about encryption and various techniques. I have read that doing a one time pad using XOR isn't secure unless the key is as long as the input, is sufficiently random, and not reused. They reference things such as the plain ... |
I have been reading around (mostly various stackexchange sites, wiki and a few blogs/forum posts) about encryption and various techniques. I have read that doing a one time pad using XOR isn't secure unless the key is as long as the input, is sufficiently random, and not reused. They reference things such as the plain ... |
I have been reading around (mostly various stackexchange sites, wiki and a few blogs/forum posts) about encryption and various techniques. I have read that doing a one time pad using XOR isn't secure unless the key is as long as the input, is sufficiently random, and not reused. They reference things such as the plain ... |
Edit: I know this isn't really a one time pad (as pointed out), though I don't really know what to call it aside from just a pad, I guess.
I have been reading around (mostly various stackexchange sites, wiki and a few blogs/forum posts) about encryption and various techniques. I have read that doing a pad using XOR ... |
How secure is using a pad (using xor) on a encrypted data, for the purpose of obfuscating/hiding the underlying encryption? |
Edit: I know this isn't really a one time pad (as pointed out), though I don't really know what to call it aside from just a pad, I guess.
I have been reading around (mostly various stackexchange sites, wiki and a few blogs/forum posts) about encryption and various techniques. I have read that doing a pad using XOR ... |
It seems to me that padding oracle attacks are mainly a concern for users of CBC mode encryption. Question: are any other [modes of operation](http://en.wikipedia.org/wiki/Block_cipher_mode_of_operation) vulnerable to [padding oracle attacks](http://en.wikipedia.org/wiki/Padding_oracle_attack)? And if so, why?
There... |
It's my first time using stackexchange!
So, I am doing a password manager in Java.
But now I am VERY confused because of the encryption. There will be the program login, where the user types its password, and it compares to a SHA512 hash. If it matches, the user logs in, if it doesnt, then the user doesnt login. ... |
It's my first time using stackexchange!
So, I am doing a password manager in Java.
But now I am VERY confused because of the encryption. There will be the program login, where the user types its password, and it compares to a SHA512 hash. If it matches, the user logs in, if it doesn’t, then the user doesn’t login... |
> …are any other modes of operation vulnerable to padding oracle attacks?
Nope, it’s purely restricted to CBC.
A padding oracle attack (also known as Vaudenay attack because it was originally published in 2002 by Serge Vaudenay) is **an attack against cipher-block chaining** (CBC) that can occur against any bloc... |
> …are any other modes of operation vulnerable to padding oracle attacks?
Nope, it’s purely restricted to CBC.
A padding oracle attack (also known as Vaudenay attack because it was originally published in 2002 by Serge Vaudenay) is **an attack against cipher-block chaining** (CBC) that can occur against any bloc... |
> …are any other modes of operation vulnerable to padding oracle attacks?
Nope, it’s purely restricted to CBC.
A padding oracle attack (also known as Vaudenay attack because it was originally published in 2002 by Serge Vaudenay) is **an attack against cipher-block chaining** (CBC) that can occur against any bloc... |
> …are any other modes of operation vulnerable to padding oracle attacks?
Nope, it’s purely restricted to CBC.
A padding oracle attack,also known as “Vaudenay attack” because it was originally published in 2002 by Serge Vaudenay (see [his paper](http://download.springer.com/static/pdf/4/chp%253A10.1007%252F3-540... |
> …are any other modes of operation vulnerable to padding oracle attacks?
Nope, it’s purely restricted to CBC.
A padding oracle attack, also known as “Vaudenay attack” because it was originally published by Serge Vaudenay in 2002 and introduced at EUROCRYPT 2002, is **an attack against cipher-block chaining** (C... |
> …are any other modes of operation vulnerable to padding oracle attacks?
Nope, it’s purely restricted to CBC.
A padding oracle attack, also known as “Vaudenay attack” because it was originally published by [Serge Vaudenay](http://lasec.epfl.ch/~vaudenay/) in 2002 and introduced at EUROCRYPT 2002, is **an attack... |
> …are any other modes of operation vulnerable to padding oracle attacks?
Nope, it’s purely restricted to CBC.
A padding oracle attack, also known as “Vaudenay attack” because it was originally published by [Serge Vaudenay](http://lasec.epfl.ch/~vaudenay/) in 2002 and introduced at EUROCRYPT 2002, is **an attack... |
To be clear, I have access to HASH(S) and as much HASH(S+K) as I want. Every string K is known. Can I use the extra information to my advantage and try to deduce S, without requiring bruteforce? Or do you still have to bruteforce but try less combinations since you have more information? |
Is it possible to deduce the value of a string when given its hash and multiples hashes of the string + other known strings? |
As in the title, given $g$, $g^{ab}$ are big elements in a prime group $Z_p$ and $b$ in prime group $Z_r$ ($p > r$, $g$ is one generator of $Z_p$). $a$ is unknown and also in $Z_r$, is finding $g^a$ a hard problem?
*update* $a$, $b$ and $ab$ are group elements of $Z_r$.. |
The [question as currently worded][1], and considering comments by its author, would boil down to: is it a hard problem finding $g^a\bmod p$, given
- large prime $p$
- large integer $g$ less than $p$ that is a generator of the group $\mathbb Z_p$ [see note 1]
- prime $r$ less than $p$
- knowledge that unknown $a$... |
The [question as currently worded][1], and considering comments by its author, would boil down to: is it a hard problem finding $g^a\bmod p$, given
- large prime $p$
- large integer $g$ less than $p$ that is a generator of the group $\mathbb Z_p$ [see note 1]
- prime $r$ less than $p$
- knowledge that unknown $a$... |
The [question as currently worded][1], and considering comments by its author, would boil down to: is it a hard problem finding $g^a\bmod p$, given
- large prime $p$
- large integer $g$ less than $p$ that is a generator of the group $\mathbb Z_p$ [see note 1]
- prime $r$ less than $p$
- knowledge that unknown $a$... |
In the padding oracle attack you have an oracle that only tells you whether a particular chosen ciphertext decrypts to a correctly padded plaintext. That oracle is used to build a last word oracle, which used iteratively can reveal a whole message.
The reason it works in CBC mode is that we can make predictable, arb... |
How to calculate time and space complexity of ElGamal encryption and decryption as there are two exponentiation operation during encryption and one during decryption? Here is my code for encryption:
main()
for(i=0;i<=d;i++) //where $g^d$
{
pow=pow*g;
y=pow%p;
}
for(j=0;j<=r;... |
What are the major theoretical and practical (if any) attacks on full TripleDES? same goes for AES, What are the major theoretical and practical (if any) attacks on full AES? I'm trying to make a list of attacks. I asked here hoping that I haven't missed any. |
I second the suggestion of a strong password based KDF, e.g. PBKDF2 or scrypt, which you use to derive the encryption key(s) from the user's password. Additionally, use authenticated encryption (e.g. either AES GCM or AES CTR + HMAC).
If you can't open the encryption using the key derived from the password they ente... |
What are the major theoretical and practical (if any) attacks on full TripleDES? same goes for AES, What are the major theoretical and practical (if any) attacks on full AES? I'm trying to make a list of attacks. I asked here hoping that I haven't missed any.
**EDIT:**
TripleDES: Brute Force, meet-in-the-middl... |
In the padding oracle attack you have an oracle that only tells you whether a particular chosen ciphertext decrypts to a correctly padded plaintext. That oracle is used to build a last word oracle, which used iteratively can reveal a whole message.
The reason it works in CBC mode is that we can make predictable, arb... |
The [question as currently worded][1], and considering comments by its author, would boil down to: is it a hard problem finding $g^a\bmod p$, given
- large prime $p$
- large integer $g$ less than $p$ that is a generator of the group $\mathbb Z_p$ [see note 1]
- prime $r$ less than $p$
- knowledge that unknown $a$... |
The [question as currently worded][1], and considering comments by its author, would boil down to: is it a hard problem finding $g^a\bmod p$, given
- large prime $p$
- large integer $g$ less than $p$ that is a generator of $\mathbb Z_p$ [see note 1]
- prime $r$ less than $p$
- knowledge that unknown $a$ is a posi... |
I was reading this [paper][1]. In the table-1 of the paper it says TripleDES (showing both 128bit and 168bit keysize) is vulnerable to Differential Cryptanalysis. It also says that AES (showing all three keysize) is strong against Differential Cryptanalysis. If AES-128bit is secure against Differential Cryptanalysis t... |
I have been reading up on the polynomial representation of the AES Sbox ( http://en.thehackademy.net/madchat/crypto/papers/aes-crypto.pdf ) and I can't get it to produce the correct output. Maybe I have a thinking mistake somewhere along the way, so here's what I did:
1. I picked a random byte: 10010101. This corres... |
I have been reading up on the polynomial representation of the AES Sbox (PDF: [“Essential Algebraic Structure Within the AES” by Murphy and Robshaw](http://en.thehackademy.net/madchat/crypto/papers/aes-crypto.pdf)) and I can't get it to produce the correct output.
Maybe I have a thinking mistake somewhere along the... |
I've just come across this piece of code in Bouncy Castle's implementation of [OCB Mode](http://grepcode.com/file/repo1.maven.org/maven2/org.bouncycastle/bcprov-jdk14/1.49/org/bouncycastle/crypto/modes/OCBBlockCipher.java):
if (N.length > 16 || (N.length == 16 && (N[0] & 0x80) != 0))
{
/*
... |
Most descriptions that explain how streamciphers work (like [the one on Wikipedia](http://en.wikipedia.org/wiki/Stream_cipher)), describe a model that boils down to a simple “$ciphertext = plaintext \oplus stream$”, where the stream is determined by a nonce and a key, while the plaintext and ciphertext do not affect th... |
Advantages of making streamcipher stream depend on plaintext? |
Merely stacking weak crypto (this is a very well-done weak crypto) inside strong crypto does not add any significant strength to the strong crypto.
I've studied interleaving crypto, and there are some cases where interleaved weak crypto would significantly strenghten already strong crypto, but AES is too hard for me... |
Most descriptions that explain how streamciphers work (like [the one on Wikipedia](http://en.wikipedia.org/wiki/Stream_cipher)), describe a model that boils down to a simple “$ciphertext = plaintext \oplus stream$”, where the stream is determined by a nonce and a key, while the plaintext and ciphertext do not affect th... |
Most descriptions that explain how streamciphers work (like [the one on Wikipedia](http://en.wikipedia.org/wiki/Stream_cipher)), describe a model that boils down to a simple “$ciphertext = plaintext \oplus stream$”, where the stream is determined by a nonce and a key, while the plaintext and ciphertext do not affect th... |
Most descriptions that explain how streamciphers work (like [the one on Wikipedia](http://en.wikipedia.org/wiki/Stream_cipher)), describe a model that boils down to a simple “$ciphertext = plaintext \oplus stream$”, where the stream is determined by a nonce and a key, while the plaintext and ciphertext do not affect th... |
Merely stacking weak crypto (this is a very well-done weak crypto) inside strong crypto does not add any significant strength to the strong crypto.
I've studied interleaving crypto, and there are some cases where interleaved weak crypto would significantly strenghten already strong crypto, but AES is too hard for me... |
I noticed that Bouncy Castle SecureRandom class uses DateTime.Now.Ticks as its seed by default. Isn't that unsafe to do? |
Is it safe to seed a random number generator from system time? |
Most descriptions that explain how streamciphers work, describe a model that boils down to a simple “$ciphertext = plaintext \oplus stream$”, where the stream is determined by a nonce and a key, while the plaintext and ciphertext do not affect the stream at all.
On the other hand, streamcipher designs like Helix<su... |
Most descriptions that explain how streamciphers work (like [the one on Wikipedia](http://en.wikipedia.org/wiki/Stream_cipher)), describe a model that boils down to a simple “$ciphertext = plaintext \oplus stream$”, where the stream is determined by a nonce and a key, while the plaintext and ciphertext do not affect th... |
Most descriptions that explain how streamciphers work (like [the one on Wikipedia](http://en.wikipedia.org/wiki/Stream_cipher)), tend to describe a model that boils down to a simple “$ciphertext = plaintext \oplus stream$”, where the stream is determined by a nonce and a key, while the plaintext and ciphertext do not a... |
When doing encrypt-then-mac, I can choose to use a [tag:hmac] as the MAC. For example, I could use a hash like SHA-256 or SHA-512 (by using it as a keyed hash) to create that HMAC.
Does it increase security when choosing a hash with a larger bit-size? Is a HMAC based on SHA-256 weaker than a SHA-512, or doesn’t it ... |
Are HMACs based on hashes with larger bit-lengths also more secure? |
I noticed that Bouncy Castle SecureRandom class uses `DateTime.Now.Ticks` as its seed by default. Isn't that unsafe to do? |
I have been reading about attacks and many of them work on specific rounds of TripleDES but not on full TripleDES. Is there any attack except brute force that works on full TripleDES? (theoretical) |
I'm very curious to know this and a bit confuse too, Case1:suppose, I have two files encrypted using AES-128bit ( using same password, same salt but different `Rfc2898DeriveBytes` objects). If an attacker does brute force attack (imagining that he finishes this)
to crack the keys, I'm guessing he needs to run the atta... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.