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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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
237 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
60 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
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1answer
79 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
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1answer
46 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
507 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
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1answer
100 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 ...
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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
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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?
22
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5answers
57k 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
869 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
119 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
83 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
131 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 ...
20
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
165 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
46 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
97 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. ...
0
votes
0answers
31 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) ...
0
votes
1answer
67 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
92 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
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1answer
555 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
76 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
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1answer
55 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 ...
0
votes
1answer
38 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
152 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
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2answers
173 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?
12
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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 ...
1
vote
1answer
55 views

AES in CTR mode. Does both parties have to know the nonce?

I'm a little bit confused. I'm using AES in CTR mode. Do i need an mechanism to send the nonce with the cypertext? Or expressed differently: does every participant has to know the current nonce to ...
0
votes
1answer
56 views

TOR and Orbot, possibility to add in dynamic AES encryption structure before data is send out? [duplicate]

I read on the documentation about the security issues on TOR, that it is ok if the website is running on HTTPS, but how about on Orbot and site that is not running on HTTPS? Even if it is running on ...
5
votes
1answer
2k views

Why does openssl enc -aes-256-cbc -a -salt increase the file size?

I'm using openssl enc -aes-256-cbc -a -salt for automated differential backups to Amazon Glacier. But I noticed that using this command increases the file size almost perfectly by 35%. In my ...
1
vote
0answers
40 views

AES keyfile size

I would like to encrypt files using a key file instead of a password. What I would do is: 1) Generate X random bits using openssl rand X > mykey 2) openssl enc -aes-256-cbc -in secretfile -out ...
4
votes
2answers
170 views

Saving Personal Information (Name, Address, Phone, Email) in MySQL Database

I'm going to build a web app for people to sign up and pay for a membership. The transaction information will all be processed through Authorize.NET but we save the rest of the information (Name, ...
1
vote
1answer
7k 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 algorithm but I don't know if 4096 bit encryption is supported and if it is a good length to encrypt data like: ...
28
votes
6answers
11k views

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 ...
6
votes
1answer
77 views

Using AES with same salt / IV - required for pattern matching algorithm

I need to securely encrypt data we are storing, but for each client I need the same plaintext to encrypt into the same cypher text. The reason for this is the data is still required for a pattern ...
1
vote
2answers
553 views

How come PBEWITHSHA256AND128BITAES-CBC-BC violates the 128bit key limit?

In my Java application (which use StandardPBEStringEncryptor by jasypt), when i use the PBEWITHSHA256AND128BITAES-CBC-BC algorithm instead of something weaker such as PBEWithMD5AndDES, i get an ...
9
votes
3answers
7k 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 ...
6
votes
2answers
259 views

Is there any reason to use AesManaged over DPAPI in this scenario?

I have a situation where my web application is going to be deployed on multiple web servers, and I'll be wanting to store some securely encrypted data on the DB servers (each web server has a DB ...
4
votes
1answer
46 views

Is there a security risk using a Symmetric-key for both encryption and HMACing

I am proposing to use an AES key to encrypt some data to send to a third party and in a completely separate operation/flow use the same key to create a HMAC of a message to send to the same third ...
4
votes
1answer
129 views

Has there been a breach of AES?

Are there any known logical flaws of AES Cryptography? I understand that you can always break the encryption by brute-force or by having backdoors, but I have not come across any sources that show a ...
8
votes
2answers
210 views

Has anyone validated if KeePass is safe to use? Does it have any backdoors?

Everyone says "the code is open source, go check it out". The truth is, I neither know how to validate the complex code nor can I understand the binaries in code or predict their behaviours. Has ...
5
votes
2answers
281 views

JSON data decryption

Context I am trying to learn more about web security through looking into how various iOS native apps work under the hood. I have been using Burp Suite as the MITM tool to sniff out the network ...
1
vote
2answers
166 views

Encrypting unique fields in a Database

I'm still a beginner to cryptography and want to know what the best practice is for solving the following problem: I'm creating an application with the requirement that a user's email address must be ...
0
votes
3answers
106 views

Is it OK to reuse the same SALT key across multiple deployments?

We are building a base application that needs to encrypt SSN, DOB, etc... The application is deployed to many customers. Is it "OK" to use the same SALT key for the AES encryption/decryption ?
18
votes
3answers
4k views

How secure is 7z encryption?

I have a text file in which I store all my bank details. I compress and encrypt it with 7-Zip using the following parameters: Compression parameters: Archive format: 7z Compression level: ...
3
votes
3answers
560 views

Encrypting USB traffic: Is RSA necessary for AES session key exchange when using pre-installed secret keys?

I need a solution to encrypt USB communication between device A and device B. I was thinking about configuring each device with a secret RSA-2048 key, which would be used to exchange an AES-256 ...
1
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0answers
77 views

OpenSSL is not giving correct result for encryption and decryption for FIPS test vector for AES -CFB1

I am running FIPS test vectors against AES-CFB. I am getting correct results for aes-cfb128 and aes-cfb8 but getting wrong results for aes-cfb1. The values being used by me for aes-cfb1 tests are: ...
2
votes
3answers
63 views

Stacking Encryptions (Stream over Block)

I am reviewing the code for a product our team developed where credit card information is stored in a local database in the event of no internet connection and came across the encryption methods. The ...