The Advanced Encryption Standard (AES) is a symmetric-key encryption standard adopted by the U.S. government. The standard comprises three block ciphers, AES-128, AES-192 and AES-256, adopted from a larger collection originally published as Rijndael.

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Using SSL for a single request

I want to use distributed cluster configured like: xx.resource.server.com. xx - can be anything from aa to zz, most of the requests will be one time. I need the connection to be secure between client ...
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1answer
191 views

Design of Initialisation Vector

I understand that an IV (initialisation vector) should be both unique and unpredictable, but I have found little guidance as to which is most important. For an AES cipher I have a block size of 128 ...
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2answers
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Is splitting up an AES Key a problem?

I'm wondering if it would be a problem to split up a 256 bit AES-Key into two 16-Byte blocks and distribute it, to implement some kind of a four-eyes-principle (you need two persons to decrypt a ...
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1answer
342 views

AES key management

I am encrypting a secret in a db field. I am encrypting using AES with a 256-bit key and a random IV per encryption. They AES key is hard coded in the code. Each IV is stored in clear in another ...
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2answers
3k views

Using AesCryptoServiceProvider in C#, should using an incorrect IV mangle just the first block?

This question was also asked on StackOverflow, but with no answers, and I thought this may be a better exchange, since I have the same question. ...
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2answers
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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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1answer
243 views

MySQL AES Encryption - Is it good idea to store 3rd Party Auth Tokens using AES Encryption?

I need some advice on MySQL AES Encryption. I'm developing an application which connects to various 3rd-Party APIs and retrieves the Access Tokens for the application users. These Access Tokens are ...
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3answers
4k views

Is multiple encryption a good idea?

I know that many encryption algorithms, while secure, have vulnerabilities. To reduce risks, would multiple encryption like this Blowfish_CbC ( Rc2_OFB ( AES128_CBC (myfilecontent))) be a good ...
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2answers
729 views

Should AES always give the same output?

I'm having trouble understanding AES and would like to know if encrypting the same text with the same key two times in a row should give the same output. Is there any salt or something that would ...
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1answer
181 views

Is there symmetric encryption like AES or Camelia with keys longer than 256 bits?

I am wondering if is there any (secure!) cipher like AES or Camelia with keys longer than 256 bits (and offering higher security than 256 bits). I have not found anything except ...
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2answers
788 views

How much does unknown PBKDF2 iteration count improve security?

We are crackers who get our hand on an encrypted file. We know the whole file is AES-256 encryption of the original plaintext file. We also know that PBKDF2 was run 1000 times on the original plain ...
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2answers
73 views

Symmetric encryption involving load balancers - can't randomize key?

I'm working on encrypting a web application's cookie. Using symmetric AES/CBC, I encrypt the cookie data before writing it out, and then decrypt it when reading it back in - the standard stuff. The ...
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1answer
296 views

Questions towards my application that uses bouncy castle crypto

I am implementing an application using bouncy castle crypto API it uses AES-CBC to encrypt files and i have some questions regarding the development of my application. I dont want to use a static ...
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1answer
180 views

Different AES 256 algorithms produce different results?

I've tried 3 AES 256-bit CBC encryption programs, and I seem to be getting different results for each one with the same 32-character password, which consists of all @ signs. They are: Polaris SSL ...
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2answers
120 views

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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2answers
187 views

question on hashing an aes-encrypted file

I am storing multiple sensitive data on a server that I do not own. The data is encrypted using aes-256 using cbc mode. The keys are only with me, and are stored securely. I am worried about the data ...
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4answers
2k views

Is 1Password more secure than an AES encrypted text file?

Are there extra measures taken by 1Password and KeePass, that make them more secure than an AES-256 encrypted text file? The database formats they use seem needlessly complex for my own purposes.
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2answers
618 views

Designing a cryptographic file-sharing protocol

As a learning project, I am trying to implement a secure way to share files with a friend over dropbox. (I am not looking for existing software, I am doing this in order to learn how to do this ...
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2answers
6k views

Recommended options for LUKS (cryptsetup)

I'm looking for recommended options for cryptsetup to create fully encrypted SSD (SanDisk SSD U100 128GB), which achive: Timing O_DIRECT disk reads: 1476 MB in 3.00 seconds = 491.81 MB/sec Timing ...
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1answer
571 views

When do I use NIST AES key wrapping?

Key Wrap constructions are a class of symmetric encryption algorithms designed to encapsulate (encrypt) cryptographic key material. The Key Wrap algorithms are intended for applications such as (a) ...
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1answer
395 views

How to encrypt by AES-Twofish-Serpent

I was wondering how to encrypt by doing a AES-Twofish-Serpent encryption. Does this mean I encrypt in AES first then after that in Twofish, and after that in Serpent (three separate encryptions). ...
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2answers
372 views

Can AES-256 encrypted data be changed?

I have a file that supposedly contains AES-256 encrypted data. The file was created using a proprietary program that claims to use AES-256. I have tested decrypting the file with an open source ...
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3answers
650 views

Ways to keep AES encryption key safe.? [closed]

I am using AES encryption to secure some sensitive data. For that i have to provide a certain key for encrypting and decrypting. It's not safe to keep the key somewhere on the server. So instead of ...
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1answer
95 views

Does padding an AES key hurt security (besides lowering the strength of the key)? [closed]

I've been reading about solitare and its weaknesses, and thinking about clever ways of hiding keys. It seems like you could encode an 52-bit AES key in the vertical orientation of cards in a deck (or ...
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2answers
401 views

7zip AES encrypted archive, padding oracle attack

I created an encrypted but forgot the password. When I attempted a pattern based brute force it said it had over a 100 trillion passwords to check. And to my knowledge that could take a few years. ...
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2answers
350 views

How to implement shamir's secret sharing algorithm using AES_ENCYRPT

I am using MySQL AES_ENCRYTP() and AES_DECRYPT() to store sensitive details in a database, and currently storing the key in a php file outside of the web root with read access only. The key file looks ...
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3answers
2k views

How can I securely convert a “string” password to a key used in AES?

I'm writing some software where I have to encrypt all files that are written to a specific folder using AES. There is one password/key that is configured somewhere, that is always used. I don't want ...
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5answers
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SSL/TLS - Distinction between self-signed cert and self-signed CA, and other questions?

I have a small personal website which I wish to serve securely over HTTPS. At the moment I do not wish to use a third party CA to sign my certs. I was reading this document on generating a self-signed ...
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2answers
115 views

Serving data from an encrypted database over an encrypted connection

There is encrypted data in the database (asymmetric FYI). It is to be viewed as decrypted on the website. The data can be sent to the client as encrypted to be decrypted on the client's computer, or ...
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1answer
299 views

Encrypton method that would encrypt alphanumeric data to alphanumeric data [closed]

I need efficient way(possibly as strong as AES or AES itself) to enrypt (only) aplhanumeric data and get out only alphanumeric data, using some known library (i don't want and intend to implement AES ...
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3answers
1k views

Javascript Diffie-Hellman and AES protocols

I am using the BigInteger Javascript library to create a symmetric key using Diffie-Hellman protocol. I want to create 128,160 or 192-bit keys. After some research, I have found out that I should use ...
2
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3answers
782 views

SSL vs Encryption

I am working on creating an android mobile application which needs to connect to a server from time to time. The application makes use of sensitive data which I would not like to get into the wrong ...
30
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1answer
3k views

Why does AES encryption take more time than decryption?

While I was studying the time consumed by some methods I found that encryption take more time than decryption. Is this right? I am using AES (the same steps will be taken during the enc and dec)
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2answers
5k views

Key size difference between AES and RSA

Can I say that 128 bit using AES provide more security than 1024 using RSA?
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1answer
639 views

Why can't a AES256-encrypted file be decrypted on machine other than the one it was encrypted? [closed]

I encrypted a file on my mac using openssl openssl aes-256-cbc -a -salt -in one.jpg -out two.jpg now if I try to decrypt it like that: openssl aes-256-cbc -a -d -salt -in two.jpg -out one.jpg on ...
2
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1answer
396 views

Can I encrypt a file incrementally?

Is there any way to encrypt a file incrementally? The problem is that I receive a file a chunk at a time via Internet (it's a client-server application and I send byte arrays via a WCF service) and I ...
2
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2answers
720 views

Login system using authenticated encryption without storing user password

I'm not a security expert, so I might be asking a silly question, but let me describe what I am thinking about. First, I know that a lot of web sites store hashed/encrypted passwords which could be ...
2
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1answer
80 views

Is it safe to derive an IV partially from the secret data if it is hashed before use?

To help ensure uniqueness of IV's used in a CFB AES-256 cipher, software I know of gathers bits from various sources including the plaintext being enciphered, and runs that through an SHA-256 hash. ...
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1answer
210 views

Should I run my password through Bcrypt before using it for encrypting a file with AES-256? [duplicate]

I need to encrypt a file with a password that can be memorized. So I was thinking about running the password through some rounds of Bcrypt before using it for AES encryption, so every time I want to ...
2
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2answers
181 views

What's wrong with using AES directly/“raw”?

When developing applications that require crypto routines, I know to use libraries like keyczar and libsodium rather than "raw" crypto routines myself. However, for the specific case of using AES-CBC ...
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1answer
333 views

Which is more secure, AES or Rijndael? [closed]

Which algorithm is generally considered to be more secure, and is AES-192/AES-256 still considered to be secure? After reading this it's lead me to belive that the Rijndael algorithm would be a more ...
0
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1answer
1k views

Using JTR to crack Skype Passwords

The scenario: coworker's Skype somehow lost his auto-fill password. He doesn't remember it anymore, and the account is hooked up to an email address that no longer exists. He's never purchased any ...
5
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2answers
3k views

Encrypting using AES 256, do I need IV? [duplicate]

I'm looking into encrypting with AES using a 256bit key, and I notice that a number of methods in various languages, for instance http://php.net/manual/en/function.openssl-encrypt.php, and I notice ...
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1answer
3k views

Different performance of openssl speed on the same hardware with AES 256 (EVP and non EVP API)

If I run openssl 1.0.1e like this : $ ./openssl speed aes-256-cbc (i.e without EVP API) Doing aes-256 cbc for 3s on 16 size blocks: 14388425 aes-256 cbc's in 3.00s Doing aes-256 cbc for 3s on 64 size ...
3
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1answer
226 views

Remote System Administration of an Encryption-Switch-Encrypted Infrastructure

I can't seem to find a decent explanation anywhere of the practicalities of remote system administration (e.g. SSH) of an encryption-switch-encrypted SAN-stored infrastructure. The environment will ...
8
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3answers
935 views

Verify Login and Encrypt with PBKDF2

I'm writing a desktop application where I'm using PBKDF2 to generate an encryption key to AES-128 encrypt the config file. The config file contains a crypo-random key that's been used to encrypt the ...
2
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1answer
515 views

Is OpenSSL AES GCM standardized?

I have been reading about the perils of not going the pages of my own encrypt-then-mac implementation, because there so many things can go awry. So decided to use EVP_aes_256_gcm. But some questions ...
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6answers
568 views

Is leaking the hash of your encryption key a security risk?

I've been trying to design a simple archive format, that allows me to just bundle a bunch of encrypted files together. The idea, I currently have is to embed not the encryption key but a truncated ...
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2answers
1k views

Questions to hybrid encryption. RSA with AES

I want to use a hybrid encryption in my application, so after reading a lot of lines I ended with this implemantation, please critizie it ;) (I want to stick to .Net) byte[] aesKey = ...
3
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4answers
5k views

RSA maximum bytes to encrypt, comparison to AES in terms of security?

What is the maximum number of bytes for encrypting a plaintext message using RSA that is reasonably secure and also efficient and would AES be better for the same size in bytes? The encryption doesn't ...