Questions tagged [aes]

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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Ownership proof scheme

I'm developing a device that will require ownership proof to activate HOTP authorizations. The HOTP codes will be used in the BLE bonding between the device and the owner's phone. I came up with the ...
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File encryption with Python and AES

I need to write a Python script to occasionally encrypt some small text files (~10 Kb) in order to store them in an insecure environment. Each file will be encrypted via unique symmetric key and AES ...
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Design of a web based password vault

I'm designing a password vault that's accessible to clients through an existing web application. The clients are small, (and mostly non-technical) businesses that aren't using password managers, but ...
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What algorithm does 1Password use for encryption, AES-GCM-256 or AES-CBC-256?

I would like to know what encryption 1Password uses. On the About the 1Password security model page, it says: Your 1Password data is kept safe by AES-GCM-256 authenticated encryption. The data you ...
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Python: Read RSA private key from file on disk and use it to create an AES Cipher [migrated]

I need to decrypt (using Python libs) a base64 encoded string that was encrypted using AES256/CBC/PKCS7: MIAGCSqGSIb3DQEHA6CAMIACAQIxggEwMIIBLAIBAoAUWwUA8cj6Bdcph9HPtFRinZS+...
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How to be sure there are only encrypted data on my backend

I am coding an online password manager as part of my apprenticeship. I have already coded the full backend to synchronize the encrypted data and a frontend that encrypts and decrypts data with AES. So ...
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Do I need to use TLS if data is already encrypted and gets decrypted client-side?

We are serving static content over the internet, and have a business requirement that the data must be encrypted at rest. Currently it is stored in AWS S3, where it can be accessed by authorized ...
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Step-by-step file encryption/decryption using user-supplied password

Let's say I want to build a dropbox clone. When users upload files they need to be encrypted. Later on, when the user needs to access their files, the application should be able to decrypt them using ...
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How to encrypt/store private key, if login is with biometrics/OTP/Sign in with Google

I am creating a cross-platform application, in which I am encrypting all data using AES-GSM. So my problem is that I want to store private keys locally on the user's device (either Android, IOS, Web, ...
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Intercepting responses using mitmproxy in Python. Problem in decryption

I have set up MitmProxy with a Python script to intercept network responses from one domain, used by a Desktop App. However, when I start up the App, I get the following series of transactions { &...
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Can aes256 be cracked with math.random

I read this https://medium.com/@betable/tifu-by-using-math-random-f1c308c4fd9d and if the key is generated with an old browser using math.random via chrome v8, could the AES encrypted message be ...
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Is there any benefit to encrypting a derived key?

I'm working on updating the encryption method of a class at work. The encrypt and decrypt methods take the text to encrypt/decrypt and a string which used to be used as a salt (this string is ...
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What is the best way to encrypt extremely sensitive and important data

I have a set of text data, that are of high importance and I want to encrypt them. Be it to keep it on a cloud for redundancy, or for an extra layer of security in my local machines. I understand ...
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What is more secure: encrypting individual files in archive or encrypting the archive itself?

Let's assume we have symmetric crypto with the same IV for each operation. From my perspective, encrypting the whole archive is better, as similar strings are compacted and the CBC will work for us ...
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Why does KMIP require to request two keys for AES-XTS?

According to KMIP user’s guide, when a client application desires to retrieve a 512 bits AES-XTS key, it should request 2 separate KMIP keys of 256 bits each. This is to support the structure of an ...
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Specification of AES-based PKCS#5 Password-Based Encryption (PBE)

recently I had a look at the capabilities of the Java keytool to create PKCS#12 containers with a protected private key. According to the standard a private key is protected using a PKCS#8 shrouded ...
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AES256 - 7zip Vs GPG

I noticed that 7zip provides an option to encrypt the contents of a folder using AES256 (Screenshot Below) and so does GPG using this command: gpgtar --output <Name_Of_The_Output_File> -v --...
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Use pre-computed PBKDF2 key with high iteration count as password

We provide web redirection based integration with our partners' web apps. The flow is something like the following, and the password is generated randomly and shared with them during the onboarding ...
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How are AES-256 keys generated using hardware random number generator?

I know about key derivation functions such as PBKDF2 which derive keys from passwords. That said, I am having hard time wrapping my mind around how AES-256 keys are generated using hardware random ...
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Are AES-256 keys essentially unsigned integers between 0 and 2^256-1 padded with zeros?

I know about key derivation functions such as PBKDF2 which derive keys from passwords. Am I wrong in assuming AES-256 keys are essentially unsigned integers between 0 and 2^256-1 padded with zeros?
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How to convert passphrase to AES256 key?

My plan is to convert a passphrase in UTF-8 ASCII-US to Unit8Array(32) then use it in: 256bitsKey = Unit8Array(32) from passphase iv = window.crypto.getRandomValues(new Uint8Array(32)); CryptoJS.enc....
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AES-256 without key stretching

It is not so difficult to create a password which is exactly 32 characters long. In this question - AES-256 Key Length Importance @Marc writes: you absolutely should not be using a password as the ...
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AES-256-GCM transfer IV and AuthTag

Question is for transfer encrypted data between two services (Like HTTP, GRPC or etc...) Can I transfer IV and AuthTag in plain, Is this approach secure? I have sample code in Node.js and I'm not ...
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How safe is AES 256bitkey encoded in HEX, Base64?

I am using CryptoJS AES 256 encryption: CryptoJS.AES.encrypt(realData, generateKey(passphrase), {iv: iv}); The secret is generated through: function generateKey(passphrase) { const salt = CryptoJS....
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If I use multiple different RSA public keys to encrypt a single AES key for distribution, how much does that degrade the encryption?

I would like to store encrypted AES-256 keys in a public location and give 100 different people access to the AES key by using each of those 100 people's public RSA encryption key to encrypt the AES ...
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Can I get AES CBC key from known plaintext, ciphertext, iv? [duplicate]

Long story short: I was using AES CBC PKCS5 on my image server, but I lost my keys (one key per image). I know the first 61 bytes (the original and the encrypted) of each image plus I know the IV, and ...
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How to correctly convert a bit key to string for aes 256 encrytion?

I am using CryptoJS AES 256 encryption: CryptoJS.AES.encrypt(string, secret); The secret is generated through: function generateKey(str) { const salt = CryptoJS.lib.WordArray.random(128 / 8); ...
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IV generation with RNGCryptoServiceProvider

I'm using RNGCryptoServiceProvider.GetBytes(new byte[16]) to generate IV's to use in AES (256 bits) encryption. For every record I encrypt, I generate a new IV. I'm also prepending each of these IV's ...
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Nonce in Aes-gcm AAD

I have some data which I'm encrypting using Aes-Gcm. Every time I have to encrypt the data, I generate a random nonce of the appropriate size, as well as an empty array for the tag data. In Aes-Gcm, ...
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Does using subkeys provide better protection in this instance?

I was thinking of implementing the following scheme for encryption of many independent files: From the password, which is given by the user, generate a master key using for example HMAC-SHA. From ...
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Reusing the IV, but not the key

There are a few questions on this site asking about reusing the same initialization vector for example for AES encryption under the same key, see for example this question. Now, let's not respect that ...
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Why encrypting with ECB block cipher mode provides different result?

I'm playing around with openssl command line to verify my understanding on block cipher mode. I read that ECB block cipher mode always encrypt the same text to the same output. AES operates on 16 ...
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7z "Copy 7zAES" algo brute force with 32 char password for when original file is available (QNAP QLocker ransomware) [duplicate]

As some in here might know, there is/was a ransomware attack going on worldwide that used 7z to encrypt all files <20MB for a ton of users world wide. Each user has a unique 32 char password (Upper ...
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In Algorithm: dh-ietf1024-sha256-aes128-cbc-pkcs7 where to get the IV?

I'm implementing dh-ietf1024-sha256-aes128-cbc-pkcs7 in golang and according to documentation I've managed to create the 128-bit key appropriate for AES (from my 1024-bit shared-key computed from my ...
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How to save AES Key in PEM file

I'd like to store a private symmetric key, aes-256, in a PEM file. My understanding is that usually these types of keys are derived using RSA/EC DH and there's no need to save them, but in my ...
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GoCryptfs on cloud

I read the audit docs on GoCryptFS website (https://nuetzlich.net/gocryptfs/threat_model/). There dragon has full information about the read write done in the gcfs partition, what does this mean and ...
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Hybrid Encryption: What is the format for storing the encrypted key and the cipher text together?

In the scenario of a hybrid encryption for which I use RSA (asymmetric) to encrypt the encryption key used with AES (symmetric) to encrypt my message, I need to store the encrypted key with (together) ...
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Get HLS decryption key from browser

How can I get decryption key for AES-128 encrypted HLS stream. In the m3u8 file, the URI for key leads to a file which is of 48 bytes which is encrypted. The stream is played by browser so it must ...
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Encryption/decryption at client or server side with hybrid cryptosystem?

I've read a lot of documentations about encryption in the last weeks and I think I now have a good idea of what system I will use for my project (standard hybrid cryptosystem using RSA/AES). However, ...
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Why does firebase encrypt with password hashes instead of storing the hashes?

I am trying to migrate off of firebase, as in doing so, you can export the hashes of user passwords. Looking at their algorithm, they do not store password hashes, but rather, they use the first 32-...
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Is using SHA256 to create 256bit secret key from bcrypt good ok?

I am trying to Use AES to store passwords for a password manager. For authentication I am already using bcrypt. As AES uses 256 bit Key can I use SHA256 to generate 256 bit key from hashed value of ...
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Key Exchange using RSA public key without a certificate

I want to share AES key using RSA. What is the recommended/widely used format for encrypting the AES key and its attributes with the public key? I know that PKCS#7/CMS enveloped-data allows encrypting ...
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Decrypt AES 128 encrypted file with a key file

I have a file which is encrypted using AES 128 and I have a key file whose size is 48 bytes. How can I decrypt the file using the key file? The key file has no extension, I opened it in notepad and it ...
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Why AES output has more size than my plaintext?

I have enciphered a vector of bytes that has 17 bytes in itself. However, When I try to enciphered with AES, AES output has a 32-byte size? What is happening here?
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Why is a password encrypted with AES and then sent back to the server together with the key with RSA (Instagram)?

I am trying to understand an encryption process on a website (Instagram). As far as I know, a public key is sent from the server to the client. Then the password is encrypted with AES_GCM_256 and ...
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Calculate AES-GMAC

I have a symmetric key and I have the data that needs to be authenticated. So one of the solution that I have in mind is to use the AES GMAC. I know there are other MAC's such as HMAC or hash ...
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Is the following a secure method for file encryption?

So the goal is to use AES-CBC-256 to encrypt the data in a file. To derive the AES key and IV pbkdf2 will be used to generate a 384 bit output using a given password and salt, where the first 256 bits ...
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Can password managers read my secure data? If no, how does sharing work under the hood? [duplicate]

All the popular password managers on the market advertise that they have AES-256 grade security. In a nutshell, the user has the master key and the password manager has the cipher-text. So the ...
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Which one to use AES : GCM vs CBC

I am planning to encrypt database fields using AES encryption. Now, this encrypted data will not transfer over the internet and will reside in our own datacenter only. From what I read, GCM mode ...
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Question regarding data encryption/decryption and sharing said keys with third party's

At work we have a pretty complex problem(for me at least) and I have no idea what a fitting solution would be. To give a bit of context, the company I work for is a data processor/provider for big ...

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