Questions tagged [ecb]

Electronic Code Book (ECB) is a mode of operation for a block cipher, with the characteristic that each possible block of plaintext has a defined corresponding ciphertext value and vice versa.

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Which encryption technique should be adopted to keep the search functionalities?

I am in exactly the same situation as described in this post. I must be able to encrypt data from a client workstation then send it to an untrusted server (encrypted at rest), then decrypt it only on ...
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recover plain text from cipher text in AES-128 ECB mode [duplicate]

I have a scenario where I do not have the key but I have plaintext 1, ciphertext 1, and ciphertext 2. Ciphertext 2 is built using the same key that was used to build ciphertext 1. Is there somehow a ...
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ECB... lacks diffusion(?)

I noticed that the wikipedia page for 'block cipher modes of encryption' states, "The disadvantage of this method is a lack of diffusion.", referring to ECB mode for block cipher encryption. ...
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Does hashing an ECB encryption with a strong hash function produce a secure MAC?

Does applying a strong hash function like SHA-256 to the ECB-encryption of a message (using some secret key $K$) produce a secure mac? For example, given a message $m$, would a simple mac construction ...
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What is "electronic" in electronic codebook (ECB)?

This is an honest question regarding terminology. I believe that I understand why one mode to use a block cipher is called a codebook. But I wonder why electronic as a work appears here? Is it fair ...
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Prove that ECB-mode of a block cipher is not EAV-secure

I know that ECB-mode of block cipher is not recommended to use as it is not secure and is not even EAV-secure. However, I still don't get how to prove that it is not EAV-secure and what adversary is ...
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Online AES Calculator

I am currently looking into how AES works and found a calculator online: http://testprotect.com/appendix/AEScalc I understand that the AES process has 10 rounds of calculations. Does this mean that ...
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Should I use ECB or CBC encryption mode for my block cipher?

Can someone tell me which mode out of ECB and CBC is better, and how to decide which mode to use? Are there any other modes which are better?
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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 ...
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In which cases AES doesn't need IV?

I was trying to decrypt a text encrypted with AES and ECB mode. I did try several keys and IV. I solved it by ignoring IV. (The IV was given, but it was maybe a distraction) My question is in which ...
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AES-ECB Reverse attack CTF [closed]

We have a key representing an SHA-256 hash in HEX, and we have the key in AES-ECB. We also have a file with plaintext to cipher messages that were encrypted with our key. How could we find this key? <...
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Is ECB mode more suitable than CBC mode while encrypting a long bit string?

I know that ECB is less secure than CBC, but will it be suitable for encrypting a long bit string?
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Byte At A time ECB Attack

This is my first post on stack overflow/stack exchange so please excuse me if I asked the question in a bad way or the format is bad. I am currently working through the cryptopals challenges and I got ...
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Help needed for IBM KCV

I found old key letters used in EFT HSMs with TDES keys, parted in two halfs. The check value printed on this letters is called IBM CV and doubled IBM CV. My newer HSM does not support this kind of ...
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Combining CTR and ECB modes to prevent attacks

In Reusing AES-CTR Keys and IVs for File Encryption, the OP was asking about a composite encryption scheme $$C_i = E_K\left(P_i \oplus E_K\left(IV + i\right)\right)$$ which is basically just a CTR ...
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AES 128-bit encryption - not getting expected results

I am trying to implement AES encryption on my own (128 bit key and ECB mode for now) and I can't seem to get expected results. From what I understand about AES algorithm is that it divides message in ...
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AES Padding (Nullbytes vs PKCS7)

I currently implement the AES(128,192,256)(ECB,CBC). Does the type of padding affect security? I just want to fill the blocks with null bytes.
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How to find Key with DES, ECB hash and plaintext [closed]

I have two ciphertexts. Encryption algorithm: DES in ECB mode. Ciphertext: 72EE3532F904CE2AAA966C723C463F294CA8AB1C11E9E0B304BBB6A8E2BD1F34 Plaintext: DetectedSpambotsRemailedMalwares Ciphertext: ...
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ECB attack to bank transfer

I have a problem with a task from my university. We have two banks and these banks are sending data in ECB mode. Plaintext and ciphertext look like this: Plaintext: ...
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1answer
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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
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Why is Byte-at-a-time ECB decryption a vulnerability?

I've been working on the Cryptopals Cryptography challenge problems, and I recently solved one where you recover a plaintext given a encryption oracle. The oracle produces a ciphertext in ECB mode AES....
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1answer
420 views

OpenSSL not producing messages of expected size

I have a 16 byte file, and after encrypting it, its size weirdly changes. ...
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284 views

How does AEAD guarantee authenticated encryption and plain AES does not?

This is a follow up to my earlier question. This is more out of curiosity in how AEAD (like CCM or GCM) works compared to encryption in other modes (like CBC or ECB). Suppose you have AES-256-CBC ...
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How can frequency analysis be applied to modern ciphers?

I am building a computer program that deciphers Caesar, Vigenere and monoalphabetic substitution ciphers. All of those are susceptible to frequency analysis. However, it does not seem to be real-world ...
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How to prove that ECB mode is not CPA secure?

I am new to cryptography and I do not know how to prove the ECB mode is not chosen plaintext attack (CPA) secure.
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What's the reason for Monte Carlo tests for block ciphers?

NIST specifies that implementations were required to create Monte Carlo test vectors for ECB and CBC mode for the AES competition. What's the reason for these tests? The only thing I can think of is ...
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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 ...
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Symmetric encryption construction (meet-in-the-middle attack)

This is a question I had from an exercise session. First we do DES in CBC encryption mode using a key $K_1$ and $IV_1 = O^n$. Then we do DES in ECB decryption mode using $K_1$. And then DES in CBC ...
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What are the length of ciphertexts when 16 bytes and 18 bytes of plaintext using ECB?

What are the length of ciphertexts when 16 bytes and 18 bytes of plaintext are encrypted with AES using ECB mode?
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Meet-in-the-middle attack (different block cipher modes)

Does a meet-in-the-middle attack on depend on the used modes for block ciphers? encryption: $C_i$ = $D_{K2}$($D_{K1}$($E_{K1}$($P_i$ $\oplus$ $C''_{i-1}$))) $\oplus$ $C'_{i-1}$ and $IV_1$ = $C''_0$ = ...
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Meet-in-the-middle attack (on custom encryption scheme) [duplicate]

This is a question I had from an exercise session. Exercise: First we do DES in CBC encryption mode using a key $K_1$ and $IV_1 = O^n$. Then we do DES in ECB decryption mode using $K_1$. And then DES ...
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LoRaWAN 1.0.2 Session Key Security

I am reading about LoRaWAN 1.0.2 specification. For the confidentiality and integrity of the comunication the protocol generate two session keys, the NwkSKey and the AppSKey (part 6.2.5 of the ...
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Can ECB be turned into a secure algorithm by adding obfuscation of the plaintext patterns?

Just to preface this I'm very new to cryptography. However, I've been reading that ECB should not be used under most circumstances due to its symmetry which allows attackers to gain information about ...
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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 ...
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ECB vs. CBC, I've seen the pictures, but what's the actual strength difference?

I hope that this is not a duplicate because I'm looking for nuance. I understand the difference between ECB and CBC for a block cipher, and I understand that ECB is susceptible to replay attacks, but ...
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Is ECB mode secure if plaintexts are guaranteed to be unique?

I've got a scenario where I need to encrypt many small (16-byte) plaintexts. I want to use AES-128 in ECB mode. Notably, each plaintext is guaranteed to be unique, though each may differ by only a few ...
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With DES, is ECB encryption mode equivalent to CBC with null IV for short data blocks?

I got to this by experimentation, but can someone maybe provide an explanation for this?
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Performing a dictionary attack on RSA/ECB with no padding

I have the exponent $e=2^{16}+1$ and modulus $n$ (154 digit number) of an RSA public key along with the ciphertext (64 bytes) encrypted using the same key with RSA/ECB and no padding. I am required ...
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Security of AES after key expansion 4-MB with ECB and CBC

My question is, how does the security depend or change if I encrypt with AES-128 in total 4-MB of Data? With Electronic Code Book Mode and Cipher Block Chaining Mode ? Does an adversary still ...
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Encrypting AES in ECB mode

I'm fairly new to cryptography and am starting to understand this weird art of Mathematics and theory. One thing I am trying to understand and do is encrypting a plaintext into ciphertext using AES in ...
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1answer
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Is AES ECB good enough for key spreading?

My apologies if I get my terminology wrong - I am new to this stuff. I am writing a routine (in c) to encrypt plaintext. I am using TinyAES to perform a CBC on the plaintext and sending a (pseudo)...
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Variation on the ECB Penguin problem [closed]

So this is an age-old example of why encrypting images with ECB is a terrible idea, since the underlying pattern of the image remains the same. Referenced from: If you encrypt an image (AES), is it ...
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Which block cipher mode to use?

I am working on securing a chat application, and I am not sure about which block cipher mode I should use. I am aware that I should avoid ECB as it's insecure, but what about CBC? I have watched ...
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2answers
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Security of AES ECB for 128 bit random data

I am using AES ECB mode to encrypt and decrypt 128 random data. I have read on drawbacks on using ECB but it seems that it is feasible to use it for random data. However my concern is that my ...
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1answer
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Manipulate encrypted file: AES / ECB / PKCS5Padding

As part of a competition I want to manipulate (or decrypt) a file. I know, that the file contains gzip compressed text and is encrypted with AES / ECB / PKCS5. I also have the plain text and the ...
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1answer
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Can I work around these padding issue in AES 256 ECB due to Reed solomon encoding?

Disclaimer: I do NOT believe AES-ECB to be at all useful for encryption. That said, due to time and bureaucratic issues that I'm not in control of, I need to use AES-ECB. I get packets of data that ...
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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 ...
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ciphertext stealing and CTR

Why Does CTR mode encryption not use ciphertext stealing?
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Key recovery after AES-ECB encryption of two blocks with some known plaintext/ciphertext

I am analysing a small, bespoke end-to-end encryption service's source code, in particular their user registration process. I am finding some interesting things going on and I am wondering if there's ...
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How to cipher bocks with RSA in ECB mode?

I'm trying to implement a very basic RSA with functions that should generate RSA keys and cipher some text. GenKey function returns a tuple ...