Linked Questions

0 votes
1 answer
2k views

Why using AES in ECB (Electronic Code Book) mode a bad idea? [duplicate]

Why using AES in ECB (Electronic Code Book) mode a bad idea? is CTR mode better? Given only these two can be used for parallelization.
  • 313
-2 votes
1 answer
154 views

What exactly is the problem with using electronic codebooks as a block cipher mode [duplicate]

I was wondering why it is a problem with using ECB as a block cipher mode
408 votes
13 answers
165k views

Should we MAC-then-encrypt or encrypt-then-MAC?

Most of the time, when some data must be encrypted, it must also be protected with a MAC, because encryption protects only against passive attackers. There are some nifty encryption modes which ...
28 votes
2 answers
14k views

Can someone explain the ECB Penguin?

I've seen the ECB Penguin used to demonstrate why ECB is not a recommended method of encryption, but I do not understand how this translates to text or passwords. Aren't the people who create these ...
  • 391
3 votes
4 answers
4k views

Would this be considered a secure password hash?

I think I've understood properly, but I want to make sure as this will involve money. Password requirement is a minimum of 16 characters and must contain one of each [Upper, Lower, Digit, Other] My ...
7 votes
9 answers
917 views

Soft question: What are examples of beautiful proofs in cryptography? [closed]

These may include any proofs, reductions, constructions, etc. For example, simple solutions to problems which at first sight seem difficult. Elegant construction that hide deep mathematical concepts, ...
  • 1,297
8 votes
3 answers
12k views

Is it possible to find the key for AES ECB if I have a list of plaintext and corresponding ciphertext?

Assume I have a list of plaintext text and its corresponding ciphertext which was created using a specific key with AES in ECB mode. Can I recover that key? If, how big does the list of plaintext ...
16 votes
2 answers
27k views

Using ECB as RSA encryption mode when encrypted messages are unique?

As I understand, ECB should not be used as encryption mode unless you are encrypting single blocks of data which are always unique and only are encrypted once. I have a collection of ids represented ...
10 votes
4 answers
5k views

Are there any benefits to using ECB over CBC?

From what I have understood about ECB and CBC, CBC is far better as it doesn't reveal any pattern. There have been several questions here about how ECB is bad: Should I use ECB or CBC encryption mode ...
  • 203
6 votes
1 answer
42k views

Why is padding used in CBC mode?

I am newbie to CBC crypto: When I try decrypt the cipher text to recover the plain text, things are not going smoothly as I face some issues in the decryption process with padding and not obtaining ...
  • 243
6 votes
2 answers
18k views

Is ECB mode safe to use with RSA encryption? [duplicate]

Firstly, bear with me, I'm relatively new to cryptography. In a recent static analysis scan of our application, one of the findings complained that we are using ECB: A mode of operation of a block ...
5 votes
3 answers
3k views

Is it possible to decrypt the 2nd byte of AES-256-CFB-8 ciphertext without decrypting the 1st byte?

I am stuck with AES-CFB decryption. Assume I encrypted plaintext helloworld (10 bytes) using AES-CFB. Now I want to decrypt the second byte ...
  • 55
2 votes
2 answers
7k views

AES encryption without salt and IV

I need to encrypt blocks of 16KiB with AES256. I have only one requirement to satisfy - If one day a hacker gets the data without the keys, he will not be able to decipher the data. According to the ...
  • 125
4 votes
2 answers
3k views

How does blocksize affect security?

I have recently read about how blockciphers and how stream ciphers work, and although I think I finally got everything right, I'm still wondering how increasing blocksize increases security.
1 vote
2 answers
5k views

Brute force, get AES keys by multiple plain-texts with their cipher-texts

I know that the encryption is AES, and I have multiple plain-texts with their cipher-texts, I don't know the encryption mode (ECB, CFB, etc ...) actually, but I know that the keys and the IV Key (if ...

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