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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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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I read ECB is bad because the same plaintext outputs the same ciphertext. Isn't that a requirement of a cipher?

In the Wikipedia article on Block Ciphers, it says about the Electronic Code Block mode: The disadvantage of this method is that identical plaintext blocks are encrypted into identical ciphertext ...
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Encrypting Keys in a Firmware-Update

I have a bootloader on a small device (Cortex-M0/M3). I want to publish encrypted firmware updates, that can be installed on the device, using the bootloader. The whole point of the encryption is to ...
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Why does .NET's ECB mode implementation append a constant block to my ciphertext?

Consider the following code and output: ...
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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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Can you tell if this ECB mode mitigation idea is “OK”?

The context: you have to encrypt passwords (reversible, for accessing external services), and also some customer data for privacy reasons, and you need to use AES-ECB mode... The idea to mitigate the ...
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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-ECB known ciphertext/plaintext attack

i'm new to crypto and am working on a little exercise to understand the weakness of ECB mode encryption. Here is the scenario. I have the plain text ...
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64 bits cipher and birthday boundaries in ECB

I am using a 64 bits symmetric ciphers (blowfish), to encrypt a plain block using ECB. The plaintext is always 64 bits long, but due to some limitations I have to use the same key (448 bits long) ...
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Is it secure to encrypt random key with block cipher in ECB mode?

If we have a random key $K$ which is 256-bit, and have a block cipher $C$ which has a block size of 128-bit. Is it safe to encrypt $K$ with $C$ in ECB mode? This problem can be generalized to given a ...
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Implementing AES-CBC (Matasano Crypto Challenge 10)

I am currently doing the Matasano Crypto Challenge to learn a bit about cryptography. In that specific challenge one had to implement AES in CBC mode. I did that and verified that encryption and ...
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Cryptool - DES (ECB and CBC ) - double encyption

So, I uploaded a text file in Cryptool and encrypted it with DES-ECB with the key FF FF FF FF FF FF FF FF. I encrypted the cipher text again, with DES-CBC using ...
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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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MySQL/MariaDB AES_ENCRYPT() - ECB mode, IV, Padding Oracle Attack Question

Multipart question all related to AES encryption with MariaDB. Strangely enough, it looks like even today MariaDB only has AES with ECB mode. MySQL allows CBC and more I believe. Anyway I'm stuck ...
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What is the usual block cipher mode that goes with CTS

I am wondering: what is the most common, or most used, block cipher mode used that goes with CTS (CypherText Stealing)? Is it ebc or cbc?
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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 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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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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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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AES ECB one more experiment

I checked the most common AES modes and I think I got the goal of them: avoid same cyper text for same plain text. However all modes except ECB have the weakness that lost part of the message stream ...
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Reordering non-block-aligned parts with DES in ECB mode

I was given a ciphertext file which was encrypted using DES in ECB mode. It is known that the plainttext that was encrypted has the following form: Each line of text consists of a payroll followed by ...
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Is the 1st Encrypted Block Less Secure Than Subsequent Ones?

It's my understanding that Electronic Code Book (ECB) produces similar cypher text for similar plaintext inputs which is not a good thing. To get around that, Cypher Block Chaining (CBC) can be used ...
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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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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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Why are ECB CBC and CFB parallelizable?

I guess I do not understand the word 'parallelizable'. Why are ECB CBC and CFB parallelizable? It would be nice if someone could explain it in a short way.
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Is it possible to break AES-128 ECB if you are given a ciphertext and a small portion of the key?

If you are given the ciphertext and the first half bytes (8 bytes) of the encryption key (key is 16 bytes in total), can you use this to break AES-128 ECB encryption and determine the last 8 bytes of ...
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Is CBC theoretically harder to brute force when compared with ECB?

Theoretically – is CBC mode harder to bruteforce when compared with ECB when assuming: we ignore computational cost for the XOR operations, and the IV is made public?
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Complexity of ECB and OFB

What is the complexity of ECB in terms of Time and Memory? and also in OFB? I can't find it in the internet, so I decided to ask it in here.
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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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Different tools return different ciphertext value for equal input

I have a Luna G5 Safenet HSM and I want to encrypt a text file containing testtest with 3DES-ECB algorithm. So in the first step ...
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Why don't PyCrypto and M2Crypto produce the same result as OpenSSL here (AES-128 ECB)

If I run the following, for openSSL: echo -n "0123456789abcdef0123456789abcdef" | openssl aes-128-ecb -nosalt -nopad | xxd and enter the key "YELLOW SUBMARINE", ...
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Using a block cipher with timestamp instead of counter

I have a system where machine A sends updates to machine B. The updates are sent over the internet, where each update is a single UDP datagram. Machine A sends a local timestamp in each update (we can ...
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Use of CBC-AES-256 to encrypt usernames

I came across some code in our project that encrypts usernames (limited to 50 chars, most are less than 10) using the following parameters: IV size is 16 bytes Key size is 32 bytes Algorithm is CBC-...
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What if we increase the key length of DES and use ECB Mode, then will we get the different output as ECB mode encrypt with the same key?

I am looking for an answer as if we have DES having 64 bit key and we are encrypting an image it with ECB mode but it doesn't encrypt well. so if we change the key length then will it effect the ...
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Attack mode for DES + ECB

Given that the plain text(P) and the ciphertext is known, and there's a random string(8 bytes)(S) concatenated to the plain text(P || S), how to go about figuring out the random string. Querying of ...
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display an image encrypted with ECB [closed]

On wikipedia there is an example of a picture encrypted with ECB: http://en.wikipedia.org/wiki/Block_cipher_mode_of_operation#Electronic_codebook_.28ECB.29 I just wanted to know how an encrypted ...
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Blowfish ECB mode: Tools for known-plaintext attack?

I'm currently dealing with multiple blowfish-encrypted files that share the same key. All are encrypted using ECB mode judging from their appearance: I don't know what the key is but I know 64 ...
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Regain 3DES ECB key, assuming I have both encrypted and decrypted text

Let's assume I've encrypted some text with some 24-byte key using 3DES in ECB mode. Is it possible to regain the key if I have both encrypted and decrypted text? (Excluding bruteforce.)
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How would an attacker perform an exhaustive key search on a block cipher using ECB mode?

Do you always assume from Kerchoff's principle, that the attacker has access to everything but the decryption key? That is, am I to assume that to perform an exhaustive key search, the attacker has a ...
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Which ECB ciphertext stealing scheme is this?

I am stuck with identifying ciphertext stealing method with the following properties: mode of operation is ECB; recommended padding scheme for this application is PKCS#7, but apparently it is not ...
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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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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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How does GnuPG compress a file and how to deal with it? [closed]

When encrypting a file symmetrically with gpg -c file.txt, when and how does it compress the file? I was working on a cryptopals challenge and wanted to test out ...
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What is the benefit of artificially padding messages? [duplicate]

For ECB, CBC, and CFB, padding is required when the plaintext does not fill out a complete multiple of the block size. However, I have heard that is good practice to pad all messages, even if the ...
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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 ...
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AES ECB experiment

Generally speaking, ECB mode shouldn't be used. ECB seems to be more of a basic building block than anything else. Because I thought it would be interesting to experiment with encryption (this method ...
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how much is secure to encrypt a password using itself (as encryption key) for storing it on an insecure media?

I want to store a password securely on a storage (suppose in a usual unencrypted file). I use this password as AES key to encrypt itself (using AES-ECB) & then store it on the media (the password ...
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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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What about using AES-ECB with random IV?

Let P1P2...Pn be n blocks plaintext, and M0 be a random IV. Then a n+1 blocks message M0M1...Mn can be constructed by setting Mi+1 = Mi xor Pi+1. Finally, we use AES-ECB to encrypt this message. Is it ...