Data Encryption Standard (DES) is a symmetrical encryption algorithm.

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Decypt des-sunos5.7 ecncrypted file by using OpenSSL in Linux

One of the shell scripts in our old Solaris 10 server uses below command to decrypt a file. des-sunos5.7 -d -u -k password enc_filename.tar.gz dec_filename.tar.gz Now we are migrating to RHEL 6 and ...
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Why is CBC-MAC insecure for variable length input?

Can anyone explain why CBC-MAC is not secure for variable length message? I read many books, but there are still some confusion. Like the highlighted parts in following pictures Slide 32: Slide ...
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DES Decryption followed by Encryption, will it produce the original text?

This is regarding DES. My question is, if a plain text is first decrypted (with the decryption algorithm) using Key K1 and then encrypted using same K1, would the result still be the original plain ...
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How to calculate cryptographic checksum using 3DES-outer-CBC mode

I want to calculate a cryptographic checksum using 3DES in outer CBC mode. As I know (and tried Googling also ) 3DES is an encryption algorithm, I'm not getting getting any information about how it ...
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Why was DES with 112 bit keys (IBM) reduced to 56?

On the French wikipedia page about DES it says that the original DES algorithm from IBM used 112 bit keys. Why did they reduce this to 56 bits? Edit: ok NSA convinced IBM but today it seems like a ...
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How does the meet in the middle attack work on double DES?

I am having trouble understanding the meet in the middle attack and how it works on double DES. I understand that on single DES the key length is 2^56 but why when using double DES is it 2^57? Can ...
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What is the difference between double DES and 3-DES?

I'm not getting the exact main point of 2-DES and 3-DES. I would like to know the difference between the two; why 3-DES is chosen over 2-DES?
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Why does my SHA256 certificate get encrypted with 168 bit 3DES?

We use S/Mime certificates for internal emails within our company. The certificates signature algorithm are all SHA256RSA with a hash of SHA256. I have confirmed the public keys are RSA(2048bits). ...
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Key Hierarchy and key Encryption

If i have two 56-bit DES keys, and I use these two key to encrypt a 256-bit AES key. Like this: K_AT encrypts K_BT and K_BT encrypts K What is the effective security of key K? Is it 2 X 56 Bits?
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Triple DES Initialization Vector: Do I use 3 different IVs?

I want to implement a triple DES CBC algorithm but I do not know whether or not I should use a different IV for every encryption-decryption or the same. I suspect the same IV should be used in all 3 ...
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Cracking DES(Unix)/MD5 ARP

This is a basic example of an Unix Pass Encryption. I have a little Hash of MD5 ARP: user50:$apr1$w7YNTrjQ$0/71H7ze5o9/jCnKLt0mj0 user60:$apr1$AIw2h09/$Ti0TRlU9mDpCGm5zg.ZDP. I need to find the ...
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32-bit Radio Voice Encryption, is it really that secure? If so, how?

I'm a student studying Electrical and Computer Engineering and a ham radio operator (i.e. my knowledge of encryption is basic). More and more, police and local government radio has become encrypted, ...
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cracking krb5 passwords (des3-hmac-sha1 and des-cbc-crc )

I'm trying to audit kerberos passwords. The available formats are des3-hmac-sha1 and des-cbc-crc but I cannot find a possibility/a tool to crack them. For other hash-types I used John the Ripper, but ...
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TLS_RSA_WITH_3DES_EDE_CBC_SHA reported as 112 bits

I am no expert in this area but after some searching I am not too sure about the solution. An external vendor doing a pentration test on our server reported that we have ...
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Why has the NSA had a hand in deciding on encryption standards?

The NSA has had a large hand in the design of at least two significant encryption standards: the Digital Encryption Standard, and its successor, the Advanced Encryption Standard. Because of their ...
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Security comparsion of 3DES and AES

Which one is more secure and least possible to be broken through cryptanalysis AES or 3DES (no matter performance)? I need to use encryption for my projects to store and secure sensitive information ...
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How to look up permutation tables in DES?

For finding out the final permutation or initial permutation in DES Encryption, we need to look up permutation tables. Taking an example: Find the output of the initial permutation box when the input ...
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What is the output length of CBC with zero input?

Given this formula for CBC encryption from 6.2 The Cipher Block Chaining Mode what is the output length of CBC if plaintext P is of length 0?
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Understanding Key Serial Numbers (KSN) in Derived Unique Key Per Transaction (DUKPT)

I have a number of questions regarding Key Serial Numbers (KSNs) in DUKPT: KSNs are 8 - 10 bytes long. Older implementation are 8 bytes whereas newer ones are 10 bytes. Do I risk being incompatible ...
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Why is there a “des-ede3-cbc” in my rsa private key?

I have created an OpenSSL RSA private key and certificate request with 4096 bit with the following command: openssl req -newkey 4096 When I view the private key with openssl asn1parse -in privkey ...
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Why two key DES algorithm provides only 80 bits security

In the wiki link, it is mentioned that due to "chosen-plaintext" or "known-cipher" attacks, two key DES provides only 80 bits of security. My question is how these attacks work and how did NSIT came ...
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Getting multiple key matches on plaintext/ciphertext pairs in double DES

I'm trying to implement a Meet-in-the-Middle attack and just to test it out I've done some hardcoding of values, which is simply this block of simple code: byte[] key1 = new byte[] { 0x20, 0x00, ...
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Find DES encryption key having input and encrypted output

Having the source string: S3nh4#1 And the generated encrypted string: csf7259aT07Rw Using this script, it identified the algorithm used to encrypt as DES(Unix) I wonder if it is possible (in ...
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DES-CBC: Two ciphertext blocks c2 and c5 are equal. Why would this leak information?

Here, suppose that we were able to observe the ciphertext that we know had been encrypted in CBC mode, then how knowing of c2 and c5 ciphertext blocks would leak information ? My professor asked us ...
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Real time application of AES and DES [closed]

I am writing a paper on reducing the power consumption of security protocols. I am having trouble identifying sources that describe real-time usage of DES and AES, and how often they are used. I plan ...
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Mapping of plaintext and ciphertext in DES

The plain text and the cipher text have a one to one mapping. Given a pair of those, can there be multiple keys used to generate the same pair? Or can a particular plain text - cipher text mapping be ...
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Do DES keys have to be random?

In stream cipher (namely the OTP ) . The pad which the plain text is Xored with has to be random to achieve perfect secrecy , or psudorandom to ensure semantic security Dose this apply to DES or ...
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How do I identify a DES encryption key in a dump file using winhex?

I've created a C# program that encrypts and decrypts a file. The encryption method is DES. The program is exactly the same as in the following link, except that the part that removes the key from ...
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How do I decrypt an Adobe Triple DES ECB-mode encrypted password?

So as you may have heard, the Adobe user database with 130 million records was leaked recently. I want to find out what password I used for the Adobe account I created to make sure that I'm not using ...
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Is my SIM card vulnerable to DES cracking?

Srlabs have recently published article stating that many SIM cards can be exploited using vulnerability in DES: [...] While the option exists to use state-of-the-art AES or the somewhat outdated ...
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How does DES provide confusion and diffusion? [closed]

I know that Data Encryption Standard (DES) provide strong security but I want to know how does it provides confusion and diffusion?
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How is the key obtained when I login via VPN?

So, I configure my VPN (let say which uses PPTP protocol), enter the server name, username and password. Then, I visit a website. Before that, my request is encrypted using AES with some key. That ...
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Why is SHA-3 (keccak) considered more secure than DES when you can attempt to crack it 3x faster? [closed]

Hash.Type....: descrypt, DES(Unix), Traditional DES Speed.GPU.#1.: 6215.8k/s Hash.Type....: SHA-3(Keccak) Speed.GPU.#1.: 20514.1k/s see: http://hashcat.net/forum/archive/index.php?thread-2085.html ...
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Is the DES “mangler” function invertible?

The DES symmetric cipher is based on a Feistel network operating repeated on 32-bit halves of the 64-bit block. The usage of Feistel means that the "mangler" function used does not need to be ...