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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Is AES-GCM recommended for SSL?

I'm looking at turning on site-wide SSL for a website I manage, and I'm wondering what the best practices for SSL configuration. I'm not too worried about compatibility with old browsers and more ...
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Security of bcrypt/sha256 key used with AES to encrypt a file

I'm looking to encrypt files using secure hashing and encryption algorithms in Python. Having used bcrypt in the past, I decided to use it for my passphrase calculator, then pass the output through ...
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Need advice on Cryptography digital files project

I have to choose a topic for my end-of-year school project and I need some advice. I was thinking of implementing an online tutorial materials (digital files) project. I have been researching on ...
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Implications of having a service account in AD use RC4 rather than AES for Kerberos?

Bear with me, I know this is sloppy, but here is the back story: We have a partner that uses Jira and is using spnego with a custom auth back-end that expects certain group membership in the token. ...
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Implementation review - Independent key, admin side and user side

The admin of the website needs to read user data. So, if the key is derived from the user pass, then the admin has to know the user pass, not exactly a good idea. The following encryption scheme was ...
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openssl: recover key and IV by passphrase

A large amount of files were encrypted by openssl enc -aes-256-cbc -pass pass:MYPASSWORD Openssl should derive key+IV from passphrase. I'd like to know key+IV equivalent of that MYPASSWORD. Is ...
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Pitfalls of SSD encryption

Encrypting an SSD is a process that is sometimes warned should be done with caution. E.g. http://en.gentoo-wiki.com/wiki/DM-Crypt_with_LUKS mentions how the SSD may keep hidden space used for wear ...
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Filling the disk with random data prior to encryption?

Filling the disk with random data prior to encrypting it will supposedly make it harder for the attacker to perform any cryptanalysis. Most sources seem to state this is because it will be harder for ...
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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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207 views

Password protection of encryption and signature keys

I would like to store encrypted backup of text files on my computer. I'm developing a python script using Pycrypto to achieve that, based on this code to use the library. (current code) The basic ...
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WPA2 Enterprise AES encryption key size?

I have recently set up a RADIUS server with EAP for my wireless router, however, I have some questions about the key size and how WPA2 enterprise (AES) works in general. I have read that in ...
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RSA and encrypted authentication

Symmetric algorithms such as AES provides modes such as GCM which can be used for authenticated encryption. Assuming that I'm using RSA instead of AES, does it still make sense to add authentication ...
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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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AES using derived keys / IVs. Does it introduce a weakness?

I'm looking for an efficient way to encrypt multiple fields in a database with AES using a single global key, used throughout a large web application. Obviously in order to re-use this key, a unique ...
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548 views

User authentication + database encryption with same password

I'm working on a private project where I need to store a users financial data in a database. I'll encrypt this data using AES, and I'll be using scrypt to generate a AES ecnryption key from a more ...
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387 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 ...
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560 views

Android and AES side channel attacks

I am working on a project that will involve symmetric AES 128 bit encrypted communication between an Android application and a bluetooth device. Are there any public AES libraries available for ...
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How can I encrypt a file with .NET and have the same file size of the original file?

I'm using .NET and I've written an awesome routine (xD) that encrypts and decrypts a file using AES256 CBC. It works perfectly, but now they told me that the encrypted file must be of the same size of ...
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I don't see how “-salt” in the openssl command line tool enhances security at all

I do this to encrypt a single file: openssl aes-256-cbc -a -salt -in file.txt -out file.enc and then type in some regular plaintext password. I do not understand how -salt enhances the security of ...
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How long would it take a single Processor with the AES-NI Instruction Set to bruteforce an AES Key?

I know that it seems like a stupid question - since it's note feasable to break AES without a quantum computer but I'm curious anyway. I read on wikipedia that the best known attack on AES-128 takes ...
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Decryption on AES when the same key and IV are used

Let's say that I have three messages being encrypted by AES-128 with the same key and IV every time. Is it possible to decrypt the key being used? And more importantly, is it possible to decrypt the ...
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Is Aescrypt a valid tool for encryption or not?

I'd like to know if Aescrypt is a valid tool, or if for a very secure protection, the only choice is to use a software like gpg, or similar. More I've another curiosity, if one doesn't want to use ...
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How does Cipher Block Chaining relate to AES?

I was reading FIPS197 for a class (found here: http://csrc.nist.gov/publications/fips/fips197/fips-197.pdf ) trying to find some sort of specific relation between CBC and AES. I guess my problem is ...
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User data encryption/decryption in a database (PHP)

I was wondering which is the best way to encrypt and decrypt user data in a database, to make it much more secure as it is possible? I was reading about AES but I would like to know if is really the ...
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Where is the salt on the OpenSSL AES encryption?

I'm interested in knowing how and where OpenSSL inserts the generated salt on an AES encrypted data. Why? Im encrypting data in Java classes and need to guarantee that I can use OpenSSL to decrypt ...
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AES CBC over TCP - when is new IV needed

I am working on a project where two devices will be communicating with AES with CBC over TCP. We already have a secure mechanism for sharing the encryption/decryption key. I am not sure if we need to ...
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How secure is Intel SSD Encryption?

Are there any known flaws in the full disk encryption on Intel 520 series SSD drives? Specifically, it seems these drives generate an internal AES key automatically, even when no password is set. But ...
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Should WPA2-AES be presumed insecure? (What is the “Hole196” vulnerability?)

I saw it mentioned in an answer here about firesheep, but I've never heard of it -- Should WPA2 be presumed insecure?
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AES Key Generation Strategy/Algorithm For Offline System

Let say I have several application that aren't connected to any network, and I have one requirement that says each application could produce a token from an input that other application could validate ...
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Does AES-192 provide better encryption than AES-256?

this wikipedia article describing AES says: Related-key attacks can break AES-192 and AES-256 with complexities 2^176 and 2^99.5, respectively. Does this mean that AES-256 is actually a weaker ...
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OpenSSL fails NIST AES-128-ECB test vectors?

I'm having trouble getting OpenSSL's ciphertext to match the NIST test vectors. Example : in "ecb_e_m.txt" from http://csrc.nist.gov/archive/aes/rijndael/rijndael-vals.zip, the first test is (in hex) ...
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Asymmetric crypto: Decrypt own messages without having private key

I have built a messages system for my website. Users can send the admin messages which are stored in the DB after being AES-encrypted. I think that using asymmetric crypto (RSA through openssl) ...
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Kik | WhatsApp - Encrypted? iOS / Android Message encryption tips [closed]

Kik says that their client is using ssl etc. But it's kind of hard to tell if the messages is actually encrypted between the devices. What i can understand is that they don't got device-to-device ...
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Protecting passphrases within an application

First off, I'm not very familiar with encryption best-practices. My use-case is simple: I'm creating an application that will be reading encrypted documents and decrypting them dynamically to do some ...
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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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Using GPG or PGP for symmetric database encryption/decryption in c# [duplicate]

Possible Duplicate: Using GPG or PGP for symmetric database encryption/decryption in c# I am looking to symmetrically encrypt/decrypt information in a database. This info consists of short ...
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Using GPG or PGP for symmetric database encryption/decryption in c#

I am looking to symmetrically encrypt/decrypt information in a database. This info consists of short pieces of information, which need to be individually encrypted when a specific method is called. I ...
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When using AES and CBC, is it necessary to keep the IV secret?

If I encrypt some data with a randomly generated Key and Initialization Vector, then store all three pieces of information in the same table row; is it necessary to encrypt the IV as well as the Key? ...
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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 ...
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How secure is AES-128 for Zip files?

Say you have a cryptographically random 8 character long alphanumeric password (A-Z, a-z, 0-9) used to encrypt a ZIP file with AES-128. Can this program: ...
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Securing AES 128 encrypted ZIPs against brute force attacks

How long would it take to brute force decrypt an AES 128 encrypted zip file if the password is 8 characters long in the range of A-Z, a-z, 1-9? Does it make any difference if .NET's System.Random ...
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What's the advantage of using PBKDF2 vs SHA256 to generate an AES encryption key from a passphrase?

I'm looking at two comprable pieces of software which need to encrypt data on disk using a passphrase. One uses PBKDF2 to generate the encryption key from a passphrase, while the other uses two rounds ...
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Is symmetric encryption vulnerable to known plaintext attack?

If Bob sends some plaintext to Alice for encryption before sending the ciphertext to Carol, can Bob deduce the key by comparing the plaintext and ciphertext assuming only Alice and Carol knows the key ...
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Is AES slower to encrypt than MD5?

Is this the right interperation of this diagram: http://www.cryptopp.com/benchmarks.html AES/CCM MiB/Second:61 Cycles Per Byte:28.6 MD5 MiB/Second:255 Cycles Per Byte:6.8 And does that ...
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What are the variables of AES?

AES is a standard encryption routine that can be used consistently across multiple languages, assuming all the variables match up. My question is, what are the variables. I am aware of the following ...
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Using PBKDF2 with AES and SHA2

I use the following inputs to encrypt using AES: UserPassword (plain text) SecretKey RandomIV I use the following inputs to encrypt using SHA512: UserPassword (plain text) RandomSalt I'd ...
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How to check for a key *and* store encrypted data?

I wish to create a system wherein I store encrypted data. Users can access this data if they have the key. If they give a wrong key, they don't get access at all. If they give the right key, they get ...
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Authenticated Encryption vs. contained and encrypted checksum/hash?

So I read through http://en.wikipedia.org/wiki/Authenticated_encryption and http://www.cryptopp.com/wiki/Authenticated_Encryption and I don't seem to be following the concept. From the simple ...
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Does the endianness used with an encryption algorithm affect its security?

I'm implementing the AES block cipher, which reads/writes data in 16 byte blocks. The implementation I'm working with usually read data in the little endian format. But in my platform the endianness ...
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Hybrid key management doing it wrong?

I'm currently working on a project that needs be as secure as possible key-management. My experience with encryption, decryption and key-management are none whatsoever so i did some research on the ...