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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2k views

Implement AES-CTR on top of AES-ECB

I using a microcontroller which only support AES-ECB encryption i.e. no decryption-mode, CBC, GCM or similar modes. However, I'm wondering if it's possible to implement AES-CTR or similar on top of ...
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1answer
784 views

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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1answer
234 views

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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1answer
2k views

AES-256-ECB to encrypt VOIP audio-stream?

I need to encrypt a live audio-stream that is being sent over the internet. The details are: The stream contains spoken language (VOIP) Only the raw stream is transmitted (no meta-data or container) ...
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2answers
179 views

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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Chosen Plaintext attack on AES in ECB mode

I am familiar with the following method for an chosen-plaintext injection attack on ECB ciphers, where I am allowed to append a block of bytes to the packet being encrypted: I inject a string with ...
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1answer
2k views

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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4answers
508 views

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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1answer
232 views

Using rainbow tables to find encryption keys of block ciphers?

Hi I have a question in mind. Let's consider a block cipher whose key length is 36 bits. The bit-length of the plaintext is 256 bits, but there are only 16 possible plaintexts $m_0, m_1, . . . , ...
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2answers
3k views

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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0answers
975 views

How can I find or reverse engineer the whitening in an AES algorithm?

I am working with this black box cryptography scheme. I know the plain text, cipher text, and everything else except how they whiten the data (or key?). Everything is 128 bit, 16 bytes. I have two ...
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2answers
431 views

Is it feasable to combine ECB and CTR block modes of operation?

Both ECB and CTR block modes have advantages over other block modes. They both support parallel encryption and decryption and random reads/writes. Yet both have major disadvantages: (I'm assuming AES ...
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0answers
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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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1answer
811 views

How can I break this block-cipher?

So we've got to do this assignment for our study, but we can't figure out what to do, can someone help? Assume that Alice and Bob want to communicate via encrypted email. To this end, they first meet ...
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2answers
1k views

Key recovery when AES ECB is used for short but repeated messages

My question is based on the specification of the protocol LoRaWAN and especially on the part 6.2.5 Join-accept message. It is said that the join-accept message is encrypted using AES ECB. This is (...
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1answer
1k views

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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0answers
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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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1answer
517 views

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 ...
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2answers
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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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1answer
182 views

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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1answer
750 views

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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1answer
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How long does it take to decrypt an RSA/ECB encrypted message?

I am working on assignment where I have specific scenarios and I am little bit struggling with this one. Alice sends and email to Bob.For this e-mail, she uses the following method of encryption: ...
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1answer
8k views

Finding key of AES in ECB mode

How many plaintext-ciphertext pairs would be needed to guess with probability, say $p=0.5$, the key $k$ of AES under ECB mode? Most of the articles that I found tried attacks on single plaintext-...
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1answer
729 views

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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1answer
416 views

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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1answer
608 views

Implementing 5 modes of operation with a hash function

Is it possible to implement any of the 5 modes of operation (ECB, CBC, OFB, CFB, CTR) with a hash function?
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1answer
759 views

Safety of AES ECB when used with openssl_seal function

I'm trying to use PHP to encrypt files with a public key. I'm using the function openssl_seal that "encrypts data by using RC4 with a randomly generated secret key." RC4 is considered unsafe so the ...
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1answer
1k 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.
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2answers
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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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1answer
398 views

Segmenting encryption to get the same results with the same key

The given examples below are dummy and in English. They are mainly for place holding as this is a concept question rather specific example based Given AES has a block size of 128 bit (16 letters of ...
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2answers
15k 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 ...
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1answer
815 views

Is it safe to encrypt random data using ECB mode?

If I have 48 random bytes, is it safe to encrypt them using ECB mode? Or is there still a good reason to use another mode like CTR, CBC, etc.? Context is this: I am creating something like a TLS ...
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3answers
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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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3answers
907 views

Known plaintext, unknown 128 bit block cipher

I have an encrypted configuration file from an embedded device which I'm trying to decrypt. The file seems to be encrypted in 128bit blocks, as changing a single option causes a 16 byte block to ...
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2answers
856 views

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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1answer
240 views

Will the complement of a 64-bit key and message produce the complement ciphertext if ECB is used in DES?

Say I have a 64-bit message/key: P1: 1011....... K1: 0101....... I run this message/key pair through DES in ECB mode and obtain some cipher that looks like the ...
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2answers
704 views

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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1answer
2k views

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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1answer
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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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1answer
157 views

Why can't I use ECB with some obfuscation for transient RAM?

I understand that ECB does not hide data patterns well. But my understanding is that it cannot be broken to "know" the underlying message. If that was the case, why can't ECB be used with some ...
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1answer
355 views

Which block cipher mode does the experts use? [closed]

I want to know which "block cipher mode of operation" does the experts use? I don't want to use ECB or CBC because add padding and padding mess up my code. So which one does the experts use. /Thanks
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2answers
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Can I simulate iterated AES-ECB with other block cipher modes?

I am trying to write some code using the Web Crypto API (http://www.w3.org/TR/WebCryptoAPI/#algorithm-overview) which provides only some of the block cipher modes for AES, intentionally excluding AES-...
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1answer
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What is Initialization vector (IV) [closed]

I am not the best cryptologer and therefore I have some questions so I learn more and get better. Heres the questions: What is Initialization vector (IV)? MUST I use it or not?
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3answers
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Why shouldn't I use ECB encryption?

I'm using Java to generate encrypted strings, and I get this warning at build time: ECB encryption mode should not be used So I'm wondering why I shouldn't use ECB and what I can use instead?
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1answer
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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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1answer
2k views

blowfish ecb with openssl doesn't give the expected result

I do the following via the Linux CLI: ...
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2answers
1k views

AES-ECB as an authentication mechanism

ECB is considered to be insecure when used for confidentiality because identical plaintext result with identical ciphertext. But what if we use ECB for authentication? Assume A wants to transmit an ...
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3answers
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Modes of operation that allow padding oracle attacks

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 vulnerable to padding oracle attacks? And if so, why? ...
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1answer
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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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1answer
1k views

Attacks on AES-128 (ECB) based on some knowledge of plaintext

I'm working with a third party protocol which employs AES-128 in ECB mode of operation to encrypt a packet composed of 16-byte blocks (it encrypts each block independently). I'm trying to determine if ...