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 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?
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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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694 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 ...
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111 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 ...
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1answer
74 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. ...
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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 ...
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2answers
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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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2answers
157 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 ...
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1answer
41 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 ...
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1answer
94 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. ...
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30 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) ...
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1answer
61 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 ...
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2answers
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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 ...
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1answer
545 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 ...
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1answer
74 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 ...
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1answer
52 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 ...
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1answer
34 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 ...
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2answers
147 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 ...
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2answers
156 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?
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1answer
2k 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 ...
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1answer
54 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 ...
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1answer
52 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 ...
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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 ...
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0answers
39 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 ...
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2answers
154 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, ...
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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: ...
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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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1answer
70 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 ...
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2answers
534 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 ...
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3answers
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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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2answers
248 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 ...
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1answer
45 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 ...
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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 ...
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2answers
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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 ...
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2answers
252 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 ...
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2answers
159 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 ...
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3answers
103 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 ?
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3answers
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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: ...
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3answers
542 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 ...
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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: ...
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3answers
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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 ...
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3answers
714 views

Steps for building a good File Encryption on Android

I want to be able to build a good file encryption on android for a cloud app. The files used are mainly pdfs, pngs, docs, audio, video, etc (all sorts of files). Edit: My constrains are that it ...
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1answer
65 views

What CryptoPP APIs Output Round By Round Results for AES Encryption/Decryption?

I created a program using CryptoPP APIs to implement AES ECB mode with a 128 bit key for encryption/decryption of user input plaintext. I know that ECB is the least secure AES mode but it is ...
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1answer
42 views

Can I modify a ciphertext created in AES with OFB mode?

Suppose a service uses AES to encrypt Cookies, of the form user=username+padding,tmstmp=timestamp where tmstmp is the expiration time and +padding is a series of zeroes to make the total length be ...
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0answers
22 views

Security implications of an “obsolete” cipher as indicated by Chrome [duplicate]

I guess this has been asked before, but what are the security implications of the below message? I've seen ciphers such as AES_128_GCM being labeled as "modern". Is this mitigated server side (load ...
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1answer
88 views

why don't we measure the strength of crypto against the cost it would take to crack it? [closed]

I hear all the time how many hours it would take to break a certain type of encryption. I think this may be the wrong metric to look at ever since scaling became an easy to implement solution. Sure ...
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1answer
101 views

Why does initial encryption take so long? [closed]

I am encrypting my new 1 TB drive using VeraCrypt and AES encryption. It estimates 9+ hours just for the outer volume to be encrypted. I assume the inner volume will take just as long. Why does this ...
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Why has the NSA had a hand in deciding on encryption standards?

The NSA has had a large hand in the design of at least two significant encryption standards: the Digital Encryption Standard, and its successor, the Advanced Encryption Standard. Because of their ...
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1answer
87 views

Security risks of symmetric encryption with compression for database data

I would like to compress data before encrypting and storing it in a MySQL database to reduce especially bandwith requirements. In the future, the DB may be accessible via a web interface. Various ...
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1answer
178 views

Strange Finished message in TLS

I've tried to understand the content of the Finished message of TLS. I'm using WireShark to capture the traffic between my browser and the internet. I noticed a "strangeness" when the chosen ...