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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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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1answer
471 views
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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4answers
1k 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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1answer
109 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 ...
2
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1answer
540 views
static IV and random keys using aes-256-cbc
Are there any security risks in using a static IV if I generate a new random KEY for each set of data to encrypt?
If I understand correctly what the purpose of the IV is in Cipher-block chaining mode ...
2
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1answer
33 views
AES in CTR mode with same random IV to create same ciphertext
I am currently working on a little project.
I am trying to generate an AES key with that I would like to encrypt a private RSA key. I have to do it this way. However, I do not want to save the AES ...
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2answers
204 views
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 ...
2
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1answer
413 views
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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1answer
943 views
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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1answer
198 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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2answers
424 views
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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1answer
3k views
Is 4096 bit good enough to encrypt data?
I need to store encrypted information in a mysql table. I would like to use the AES algoritm but I don't know if 4096 is supported and if it is a good length to encrypt data like: credit card, email ...
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3answers
258 views
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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1answer
81 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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4answers
169 views
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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2answers
134 views
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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1answer
185 views
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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1answer
229 views
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 ...
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1answer
90 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 ...
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2answers
220 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 = ...
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1answer
301 views
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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1answer
277 views
Weakness of AES OFB mode
I found these comments regarding AES OFB Mode "This mode is a slightly less common mode, quite similar to CFB above, but which should not be used as a stream cipher due to inherent weaknesses when the ...
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1answer
397 views
aes cfb 128 decryption /encryption problem between Erlang and PHP
Update 2 - it works
Thanks to Tom Leek for his answer.
The CFB mode of mycrypt for Rijndael uses a 8-bit feedback loop and not a feedback loop the length of the key/iv.
You have to force it to use ...
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1answer
82 views
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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1answer
105 views
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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0answers
57 views
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 ...
0
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2answers
530 views
Why does OpenSSL not include AES-256-GCM? [closed]
I'm trying to implement AES-256-GCM in Ruby.
Ruby's OpenSSL wrapper library and aead library both clearly seem to believe that OpenSSL itself supports this.
However, neither 0.9.8r (which I had ...
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2answers
188 views
Where do I securely store application-specific symmetric key?
I am writing an application App1. This application uses SQLite database and I plan to encrypt it using AES256. For symmetric encryption I need a key, which I need to store somewhere.
From a similar ...
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1answer
141 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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1answer
247 views
Can active attacks really decrypt a particular AES-256, CBC, PKCS#7 encrypted file?
I recently found out that active attacks are a threat against AES-256, CBC mode, padded with PKCS#7 (the CBC mode in particular. I should supposedly change to EAX to guard against these attacks).
...
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1answer
100 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 ...
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1answer
112 views
What AES mode does SQL Server 2012 use?
I looked at this link that shows how to encrypt a SQL column via a certificate (RSA??) and AES256.
I created a dummy table (script at GitHub) intentionally using identical plain text (Credit Card = ...
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1answer
333 views
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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1answer
407 views
How does PKCS#7 padding work with AES-256, CBC mode?
I'm a bit confused with AES-256, CBC, and how it works with padding (PKCS#7).
Whenever I encrypt data of multiples of 16 bytes (the block size), extra 16 bytes are always padded at the end.
For ...
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1answer
93 views
Key distribution advice
I have been thinking for days about that problem! The application is based on a student system management. I am implementing database encryption on a column level and The encryption occurs at the ...
0
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1answer
139 views
AES encrypt secret key with plaintext
We need to be able to retrieve password. Hashing is one-way, we can't do that.
So we ended up using AES.
We want to know if the following schema is safe or not. I am only familiar with modulo PK ...
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1answer
73 views
Securing the SOAP Messages
One of my clients wants to encrypt few sensitive information which will be transferred through webservices / SOAP.
My client has the following suggestions:
Encrypt the sensitive data with AES ...
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0answers
116 views
Is it possible that AES could be broken? [closed]
Much like DES was broken for years, but never truly released to the public until quite some time later. I know that AES was more open to the public when it was initially developed, and many proposed ...
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1answer
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What mode of operation is secure for block ciphers?
as RC4 is not secure and AES-CBC is same thing the only solution is using EAX mode for AES. but why mozilla NSS don't support EAX mod ? is there any secure EAX implementation ? and why wikipedia says ...
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1answer
182 views
Cascading Encryption Algorithm using mcrypt or GnuGP
I'm trying to a cascading cipher encryption algorithm to encrypt a textfile via mcrypt. I'm essentially trying to emulate the behavior of TrueCrypt, where it can cascade two or three different cipher ...
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2answers
734 views
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 ...
