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 encrypting a password with itself more secure than SHA1?
This isn't really a practical question, but more a question of curiosity. I heard a CS professor recommend stepping up from md5ing passwords not to SHA1, but to AES encrypting the password using ...
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702 views
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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662 views
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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Wheres the salt on the openssl aes encryption?
Im 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 them
...
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1answer
466 views
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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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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294 views
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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246 views
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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6answers
275 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 ...
6
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741 views
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
...
6
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2answers
108 views
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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478 views
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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1answer
584 views
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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1answer
293 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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4answers
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Encryption - should I be using RSA or AES?
My model is one where I have several clients which wish to speak with some (but not all) of the other clients.
All messages will be sent through a server.
Only the two clients communicating with ...
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322 views
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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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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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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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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3answers
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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 ...
5
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3answers
335 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 ...
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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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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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3answers
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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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AES CBC padding when the message length is a multiple of the block size
Assuming that a 32-byte plaintext is encrypted by AES 128 CBC - is it mandatory to add 16-byte padding, according to the different padding schemes?
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How less secure is an encryption if we know something about the original data?
I have a number of files encrypted with a key derived from a password. In line with standard practice, I use a random salt and password and do many PBKDF2 iterations to obtain an encryption key and ...
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205 views
How to correctly implement AES in a backup application
I am writing a back-up application which should have the feature of encrypting the back-up. It must encrypt file data, paths and filenames. The application is being written in C# (.NET). Target is ...
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824 views
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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Incrementing Initialization vector by 1
Suppose that we do not generate initialization vectors randomly (using AES in CBC mode). Instead it is initially all zeroes and we increment it by 1 each time a message is encrypted. How can this ...
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372 views
After How Much Data Encryption (AES-256) we should change key?
Considering AES-256 encryption, what is the maximum amount of data should be encrypted with one key? Does Block cipher modes/IV/counters also governs the limit?
If say the maximum amount is 50GB, ...
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1answer
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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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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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Is it safe to have the salt equal to IV?
If I'm using AES-256 CBC to encrypt, getting the 32 byte key using multiple iterations of the PBKDF2 function with a 16 byte salt, is it safe for me to let IV be equal to the salt?
(Edit: The salt is ...
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Confidentiality and integrity for web session
When the client authenticates with our service, he is issued an opaque "token". This token includes the information, that identifies the client and some other information about the client ("payload"). ...
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How X509 Certificates are used for Encryption
I have small doubt regarding the process of X509.
I am aware of OpenPGP Encryption/Decryption, where we generate the public key and private key. We can share the public key to vendors and they can ...
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LastPass One Time Recovery Passwords--How?
The LastPass password manager stores One Time Recovery Passwords locally in each browser you use the plugin with:
http://helpdesk.lastpass.com/account-recovery/
My question is, how can you have more ...
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1answer
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Key length and hash function in PBKDF2
On this page:
http://www.ruby-doc.org/stdlib-2.0/libdoc/openssl/rdoc/OpenSSL/PKCS5.html
they make a statement that strikes me as rather weird:
Key Length
Specifies the length in bytes of ...
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TrueCrypt -vs- MacOS encrypted sparse image - equally secure? Other alternatives?
I'm currently trying to find my personal best solution for storing passwords and other sensible data. Recently I've used 1Password on iPhone and Mac but I'm not really satisfied with its predefined ...
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Where can I find information about how to implement Intel embedded AES256 encryption?
I heard this can really speed up encryption performance, but I can't find any good information about how to implement it.
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187 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 ...
3
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2answers
137 views
Remedy for not having filled the disk with random data?
Filling a large HDD with /dev/urandom prior to encryption can be extremely slow (even with netcat, multiple instances in parallel, etc) and for this reason I'm sure a lot of users skip this advice ...
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1answer
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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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1answer
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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 ...
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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 ...
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2answers
780 views
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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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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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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Slow down symetric encryption
I'm developing a program in Java. In one step data should be encrypted and exported in a file.
As of now we are encrypting in AES-256
I want to slow down a possible brute force attack as much as ...
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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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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 ...
