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.

learn more… | top users | synonyms

1
vote
2answers
96 views

Diffence between AES-128 CMAC & AES-128 ECB/CBC?

Automotive standard for encryption use to talk about following algorithm AES-128 CMAC & AES-128 ECB/CBC. AES-128 CMAC use to provide Security service Authenticity AES-128 ECB & CBC used to ...
-7
votes
1answer
111 views

Is webkey a reasonably secure authentication system?

I just created Webkey in the last couple days. It's built to do client-certificate auth without using the (in my opinion unusable) client-cert functionality built into browsers. It would allow single-...
7
votes
2answers
57 views

Are any inherently insecure AES-CBC keys or key-IV combos known for properly generated random values?

This is mostly a theoretical question. I am using AES128 CBC to encrypt small files. Both my keys and my IVs are randomly generated per file using iOS's secure random value generation (...
2
votes
1answer
109 views

Why does this key get Base64 encoded prior to use?

I wish to have my server encrypt messages to clients who have each provided the server with an RSA public key, as well as having the clients authenticate their messages to the server using their ...
3
votes
1answer
58 views

Is symmetric encryption with one time pre-shared key secure?

Suppose I have a secure channel between client and server, with proper certificate validation etc (actually, ssh session). I want to establish a secure connection between my own application on a ...
0
votes
0answers
28 views

when/how does an encrypted volume .dmg change to reflect the file system it stores

I'm trying to verify that storing a .dmg file stays encrypted while only the mounted file system is unencrypted (see here). My thought was to create a .dmg containing a text file, make a copy of the ....
6
votes
2answers
1k views

Can I use SHA-512 hash as AES key?

I want to combine hashing and encryption for better security. So can I use a hash key generated from SHA-512 as a key in AES. For example, I have a password "secret", I calculate SHA-512 hash for it ...
0
votes
1answer
54 views

OpenSSL_encrypt returning an incorrect cyphertext?

I am trying to use the openssl_encrypt function in PHP, this is my code: <?php $message = hex2bin("00112233445566778899aabbccddeeff"); $key = hex2bin("000102030405060708090a0b0c0d0e0f"); $method =...
6
votes
3answers
105 views

What is the benefit of adding data encrypting key then store it (encrypted) along with data

To protect user's sensitive data, I am considering the following 2 approaches: Create 1 data encrypting key (DEK) for each user, use it to encrypt (using AES CBC mode with a random IV for each ...
2
votes
2answers
67 views

How does KEEPASS store images, videos and attached documents/items? [duplicate]

I have read quite a bit about KEEPASS and how it encrypts passwords. However, the more I read about it, the more I find how it generates and stores passwords - the methodology provided as well as the ...
2
votes
2answers
40 views

Could I use a TimeStamp also as IV?

For an academic application, I use AES-GCM to encrypt my frames between 2 parties. To enhance security, and reduce the possibility of replay, I'd like to use a TimeStamp in my frame exchanges. But, ...
3
votes
0answers
79 views

How to safely store the most recently used encryption password for subsequent reuse in an app?

Let's say I have a mobile app that can save photos inside password-protected AES-128 encrypted PDF files. For convenience, I want the user to be able to encrypt a file using the previously-used ...
17
votes
3answers
18k 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 ...
1
vote
0answers
25 views

Cryptography basics (in the context of AES256) [closed]

Bit of a noob question and a fair bit of Googling didn't help. I understand that the current encryption standard is AES256. A few questions 1) Is the point of this (and other encryption techniques) ...
1
vote
0answers
72 views

How to decrypt the my 1Password Vault without using the 1Password App?

I would like to know, how someone can decrypt his 1Password Vault without using the 1Password app. It should be feasible. Right? In a nutshel, My Master Password is the only "AES key" that my logins/...
3
votes
4answers
6k views

When should I use symmetric encryption instead of RSA?

I'm currently using GPG RSA keys to encrypt binary files. Many people recommend using symmetric keys to encrypt large files, and then encrypt the symmetric key with a public key. At what file size ...
5
votes
2answers
188 views

Is AES 128 encryption weak for very small payload size?

If I have a payload of e.g. 8 bits and I want to encrypt it using AES 128, I will need to add some random padding to make the plaintext 128 bits long. Does this padding affect the security of AES?
69
votes
3answers
7k views

Will quantum computers render AES obsolete?

This is a spin off from: Use multiple computers for faster brute force Here's at least one source which says that quantum computers are on the way to being able to break RSA in the not too distant ...
27
votes
3answers
4k views

Use multiple computers for faster brute force [duplicate]

I've watched Mr. Robot lately and can't stop thinking why it was so hard to decrypt files encrypted using AES encryption with a 256-bit key. Let us say the only method to find the key is through brute ...
11
votes
3answers
6k views

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 ...
4
votes
1answer
144 views

How secure is my software for file encryption with AES-256?

I'm working on a project to build software for file encryption with AES in Java, it's operation is quite simple, but I was wondering if it is really safe. The program prompts the user for a ...
167
votes
8answers
27k views

Why can't the FBI read the key embedded in the iPhone's secure chip/ROM directly from hardware (silicon)?

As far as I understand, the 4 digit passcode is combined (in some fashion) with a key stored in secure read only memory (e.g. secure enclave chip or similar), where it is directly embedded into ...
3
votes
2answers
238 views

Am I encrypting and storing an array of user-details correctly?

I came up with a user-details-storing procedure that was, in the beginning, based on actual security-literature – but then I just kept writing without really doing all the cross-checking I should have ...
0
votes
1answer
63 views

How to make a good choice between Symmetric and Asymmetric [closed]

Here and there and read a lot of articles and blog posts titled "Difference Between Symmetric Cryptography and Asymmetric Cryptography". But inside of them they are answered "What is Symmetric ...
0
votes
1answer
99 views

FileVault 2 FDE and BoxCryptor are safe to use together or they have conficts?

Assuming that someone has a Mac and uses FileVault 2 FDE (256-bit AES key) and uses the BoxCryptor (256-bit AES key) for the clouds like Dropbox/GDrive/etc and or some other folders. FileVault 2 uses ...
1
vote
1answer
51 views

How is hash used with AEAD-based ciphers in TLS? [duplicate]

Look at this cipher: ECDHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH Au=RSA Enc=AESGCM(128) Mac=AEAD It uses AES-GCM for encryption and data origin authentication (according to RFC-5288), so no ...
2
votes
2answers
530 views

Practical steps for encrypting an encryption key for data stored in MySQL

So I'm working on my first project where user data is stored as encrypted using the user's password as (part of) the key. I have read many similar things about best practices, but the details seems to ...
1
vote
1answer
109 views

what is the best way to know if the entered decryption key is correct?

I was searching for a way to store the encryption key of AES_ENCRYPT and found a good answer here: where to store a key for encryption However, now I am trying to use "Type in the encryption key when ...
-7
votes
2answers
5k 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 ...
5
votes
3answers
5k 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 ...
0
votes
0answers
19 views

Is cryptsetup luksFormat -y --cipher aes-xts-plain --key-size 512 /dev/sdax a insecure setup for luks [duplicate]

Is cryptsetup luksFormat -y --cipher aes-xts-plain --key-size 512 /dev/sdax insecure. If so why and what setup would be good for keeping corporate information safe?
23
votes
5answers
59k views

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 ...
4
votes
0answers
1k views

Why does Java allow AES-256 bit encryption on systems without JCE unlimited strength policies if using PBE?

It's fairly standard knowledge that due to the cryptography export controls, Oracle JRE ships with "limited" cryptographic strength enabled as listed in the JCA Documentation. For AES, the default max ...
1
vote
2answers
133 views

Length of AES “plain text” when decrypted with wrong key

If I encrypt a text X using key A with the AES algorithms, and then decrypt the result using key B, would the obtained plain text Y length be the same as X's? If the answer is no, is there any ...
0
votes
1answer
99 views

MySQL AES_ENCRYPT Logs Output

Need: I need to be able to store AES encrypted user data (journal entries) in my database and those entries need to be plain-text searchable. Issue: MySQL outputs queries to its logs in plain text. ...
1
vote
4answers
147 views

About the AES algorithm key and ciphertext

I have the two following questions about the AES algorithm: A- Does the key need to follow any specific pattern apart from length or can it be a completely random string? So, if I select 16 random ...
22
votes
2answers
8k views

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? ...
2
votes
2answers
175 views

Is my sending of encrypted information secure?

Please bear with me as I am not an expert in security. I have a server and a client. On the server I am encrypting a very secret message (using AES256-GCM to hide the information and protect it's ...
1
vote
1answer
53 views

Can SSL using Blowfish cipher be considered strong enough?

I use OpenVPN to connect to a public VPN. Sometimes I connect from my college campus (it's fully open to alumni) and when this happens I can only use TCP SSL because the college network has a security ...
3
votes
1answer
102 views

How can I mitigate against chosen plaintext attacks for AES ECB?

I am developing on a platform where my only encryption option uses AES ECB. The encryption is used to protect parameters that the user can set, and so it susceptible to a chosen plaintext attack. It'...
0
votes
0answers
39 views

Creating iv parameter in AES encryption

The algorithm that I thought for creating aes key and iv is: Get two values from a certain elliptic curve point that agreed before by using asymetric encryption.(x,y) Aes.Key <- HASH(x) (string)...
0
votes
1answer
70 views

Which ciphers produce random cipher text?

I already know AES produces a "random" output. 5e4e6440826d6afc4535fbf078455f791159701a9df624ddd4e4dda84523b6a7 Its cipher-text doesn't follow a pattern and is indistinguishable from noise. Is ...
3
votes
2answers
97 views

How can I create a secure random key for AES?

I need to generate a lot of shared keys for an AES method which uses in various condition, my concern is how can I generate unpredictable keys? I've had some research on Cryptographically secure ...
1
vote
1answer
577 views

256 Bit Key into AES 128 same output as 256 Bit Key into AES 256

I have two different crypto libraries I created, one is in java and uses the standard built-in java crypto libraries. The other uses openssl and has been wrapped in java through the JNI. I'm ...
5
votes
1answer
81 views

Why is the Key Derivation Function important?

Let's consider this openssl command : openssl enc -aes-256-cbc -pass pass:PASSWORD Why is it important to have a good Key Derivation Function? This answer to another question suggest that GnuPG is ...
1
vote
1answer
60 views

How does AES-GCM handle large blocks with a 128 bit key?

I would like to apply AES-128 byte encryption on GCM mode. I know the logic to apply AES_GCM using 128 bit data. But I have a larger data to encrypt (Not necessarily multiple of 16 bytes). As the AES-...
0
votes
1answer
44 views

In NTFS EFS how is the symmetric key (FEK) generated?

I have some old backups that are encrypted using windows EFS and I no longer have access to the certificate used to encrypt the FEK symmetric key included in the files but I do have the password, user ...
1
vote
2answers
163 views

Extract a key from an AES black-box?

I'm trying to figure out how a given executable works. I know it's using AES-128 to encrypt and decrypt, but the specifics of the code are unknown. I can get the executable to encrypt and decrypt any ...
-2
votes
2answers
176 views

How are people still copying and redistributing DRM-protected music

...when DRM-protected material is encrypted using the AES cipher, which there are currently no efficiently computable cracks for?
13
votes
1answer
3k views

What's the hash for in ECDHE-RSA-AES-GCM-SHA?

Presumably the SHA is for deriving the AES key from the shared secret. Where else is the hash used? ECDH just does ECC (no hashing). RSA does masking and padding but this doesn't involve the ...