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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In AES GCM, would using different nonces that are close reveal data?
Starting from a known nonce, AES GCM uses a counter to sequentially generate new numbers that are the input to the encryption function. If by chance two nonces from two distinct runs of AES GCM were ...
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What's a good way to append a nonce to ciphertext in Python for AES GCM in Python?
I'm not a security expert, so please excuse this question if it's silly, but I would really like an answer. I am using AES GCM to encrypt and would like to combine the randomly generated nonce with ...
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Using PBKDF2 in combination with AES-KW defeats usage of BCrypt password hashes?
We are currently implementing envelope encryption for our app. That means, we need to derive a key from a user's password, which then will be used as a key encryption key(KEK) to wrap another key ...
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Any information on the encrypted Knoppix user data file system (knoppix-data.aes)?
I remember about 90% of my password used for encrypting the persistent user data file system (stored as knoppix-data.aes) while setting up Knoppix a few years ago and would now like to explore the ...
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Best way to symmetrically encrypt multiple files using a password
I would like to encrypt many files using symmetric encryption such as AES256, using a single memorised password.
I was planning to use gpg but gpg symmetric encryption does not work with --multifile ...
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Is the example in the QUIC spec for header encryption wrong, or have I missed something?
In the QUIC spec, they've provided an example of header protection:
https://datatracker.ietf.org/doc/html/rfc9001#name-sample-packet-protection
They've got the following process (paraphrasing):
hp = ...
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Impact of using the AES-GCM key as AEAD associated data
Will using the AES-GCM key as AEAD associated data potentially weaken the security or bring any adverse impact?
Before this question, perhaps I should ask, can an attacker extract AEAD associated data ...
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How can I ensure nonrepeating IV with AES/GCM encryption?
I'm trying to encrypt files before storing them on my hard drive using AES/GCM encryption in Java. I currently have the following code:
byte[] iv = new byte[GCM_IV_LENGTH];
SecureRandom random = new ...
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How to verify authentication tag during chunked AES-GSM-128 decryption
Due to there are large encrypted files we are dealing with, we can't afford to keep entire file in memory during a decryption process.
I've implemented the algorithm of chunked decryption of AES GSM ...
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Omit IV for AES128-CBC when requiring to always get the same ciphertext encrypting random IDs
Imagine having images stored in a system with their 256 bit hash (BLAKE2b) as their unique ID. We want to produce a URL for each image, something like:
https://host/images/cleartext-image-ID
In order ...
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Best Practices for AES: Fixed Key with Unique IV vs. Unique Key with Fixed IV
I'm working on implementing AES256 encryption for file security and am considering two different strategies:
Using a fixed key with a unique initialization vector (IV) for each file.
Using a unique ...
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Login with roles without internet
Disclaimer: question orignally posted here but i was encouraged to ask it in this stack instead.
Introduction part
I'm writing an application that requires authentication to be used, specifically the ...
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Why Ransomware generate keypair in victim?
I read this answer Ransomware encryption keys and understood how wannacry works. But I still have a question: as I understand, the hacker will put the hacker's RSA public key in the malware, the ...
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Password-based encryption: keeping the user logged in without entering password again
Context
I have a system where some of user's data is encrypted via AES. Each user has their own key K. When the user creates an account, the K is generated and encrypted with a key derived from ...
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Assembly routine for AES CBC encrypt
I'm assuming that OpenSSL is just using these functions here. page 66 is CBC
https://www.intel.com/content/dam/develop/external/us/en/documents/aes-wp-2012-09-22-v01-165683.pdf
Can I just generate a ...
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Can token decryption endpoint response codes variability lead to security vulnerabilities?
To clarify the question, here's our case:
We generate encrypted tokens by applying AES-CBC (256 bit) and Base64 to payload:
encrypted_token = Base64.encode(AES_CBC_256.encrypt(key, iv, payload)).
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MbedTls - keeping context private?
Let's assume we're running on mbed system with internal and external RAM. Dumping external RAM is much more easier for attacker on such systems when debug ports are locked.
I'm wondering if the ...
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Same output of KDF for Alice and Bob?
Alice and Bob use the same password which will be used in a KDF like PBKDF2_HMAC or Argon2id to generate a AES-key. The problem is that Argon2id generates a different output for the same password, ...
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How to get a 12 bytes authentication tag in AES-GCM
i want to generate a 12 bytes authentication in AES-GCM. my code only give me an output tag of 16 bytes. i have tried to use the min_tag_length but it rises an error.
can i get your guidance, thank in ...
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How can I understand the zip2john hash format?
I had a .zip file that was apparently encrypted with AES-256 deflate.
7z l -slt archive.zip | grep Method
Method = AES-256 Deflate
Then I used zip2john to get a "hash" out of it:
archive....
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Does a signature service provider level digital certificate for electronic signature comply with eIDAS requirement for Advanced Electronic Signatures?
I have some basic questions regarding eIDAS and 'Advanced Electronic Signatures'.
Say, if I create a product under my company Acme Inc that offers a simple electronic signature where I sign every ...
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What is the best way to encrypt asymmetric metadata?
As a hobby project I'm thinking about how to write a secure chat where even all metadata are encrypted so that it is impossible to leak any (meta) information by design.
My basic idea is right now:
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Backup to a remote Encrypted APFS drive mounted through Samba. Is this a sound plan?
Say I have a remote machine (something like a VPS) that I have no physical access or physical authority over other than a user on it (with root access). However, I'd like to do Time Machine backups on ...
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AES mode for reusing same keyset
I'm building a sharing protocol where users share data. To make it so only those authorised to read the data can do it, I'm using AES256 encryption. Every authorized person has a keyset (IV & key) ...
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Is there any benefit of encryption if the password is known?
Is there a benefit of encryption of a file (for example with AES-GCM), if the password is included alongside the encrypted data?
I know it sounds like a useless question, but I am curious about its ...
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Recommended temporary key size for communication
What I'm going to do is use AES-256 encrypted network communication to agree upon a pseudo-random key for further communications between two peers, so that every "session" utilizes a ...
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Is rsyncrypto secure?
My information security model right now is "if you want the data that I am storing on the cloud, you can have it" and I would like to change that to "if you want the data and have a $5 ...
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How to form the IV and Additional Data for TLS when encrypting the plaintext
When using AES GCM for encryption within TLS and referring to the below diagram:
Is iv[0:3] the fixed IV established from the handshake and iv[4:11] are the current (write) sequence number + 1?
For ...
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AES ECB cookie bypass
I am currently participating in a CTF Challenge and have reached a stage where I discovered a "log_admin" page. This page generates a cookie that is encrypted using AES 128 ECB. I obtained ...
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Why AES256 with SHA384 in TLS [closed]
Is there any concrete/solid rationale for this choice of cipher? Seems to be the default when I connect via TLS1.2 to an Apache2 server (whatever latest version on Debian 11) with configuration lines ...
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Using hashed trigrams to search over encrypted data
For practice, I write let's call it a notebook app that stores users' notes in AES-encrypted form. For encryption, I use a password-based intermediate key technique as described here. Actually, the ...
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Mifare Desfire authentication process / cloning protection
I am trying to write a small explanation for a customer, who wants to understand why his Mifare Desfire transponders are safe from being cloned.
I was trying to search for an easy scheme or text that ...
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How to decrypt SSHv2 using AES-256 session keys from memory dump?
How to decrypt the plaintext contents of an SSH session from a PCAP file and SSHv2 AES session keys from a memory dump.
I have the full PCAP for the SSH sessions, including the initial handshake and ...
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Is using weak random numbers for the initialization vector of AES just a theoretical issue?
I'm the maintainer of pypdf, a Python library for reading/manipulating PDF documents. I recently discovered that pypdf used random instead of secrets for ...
Generating the initialization vector (IV) ...
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Is it possible to generate a read-only key for a symmetrical encryption (AES)?
I am working with hardware that can only encrypt with AES. The problem with this is that the message must be publicly verifiable on the blockchain, without the encoding key being exposed. This is the ...
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Where is the 8 byte explicit nonce for decrypting AES GCM within TLS?
I'm confused how to retrieve the remaining 8 bytes of the nonce (to combine with the 4 bytes established during the handshake) to generate the 12 byte IV to decrypt AES 128 GCM.
RFC 5288 "AES ...
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Generating AES 256 key from ECDH P-384
Is there anything wrong with hashing(with SHA256) the shared secret generated by ECDH that is 384 bits long and using that as the AES key? Is there a difference between that and, say, truncating the ...
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javascript: how to apply block cipher to byte stream
I am writing browser javascript that has a pre-shared key with nonce, and creates a binary websocket connection. How can I apply block encryption-authentication such as AES-GCM to the messages?
Is it ...
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Symmetric key importance During encrypt and decrypt [closed]
I am performing a small command line operation the goal is to generate a symmetric key using openssl and store the key in TPM FAPI keystore.
After modifying the symmetric key, the decryption should ...
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Strongest symmetric algorithm in 2022 [duplicate]
I'm curious about the best encryption algorithm for encrypting my files in 2022? I thought it was a good solution to encrypt my private key with AES-256 but I decided to ask here and choose better ...
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AES Encryption as XSS protection for url parameters?
So, I found a website that uses AES encryption to prevent XSS and I'm wondering if this approach is inherently flawed.
It has an endpoint like execute.php?code=encryptedPayload which de-crypts the ...
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Generate AES-256-GCM key
I'm using aes-256-gcm encryption. I used a sample key provided in the docs and it works fine.
I also tried a key generated from here and it works fine. There's no option to specify gcm here yet the ...
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How to encrypt peer data exchange?
The situation currently is as follows:
All our devices in the same network broadcast their state (alongside with unique IDs) over the network. They also listen in for broadcasts of others. Everything ...
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Can parts of WebCrypto AES-GCM be reused between encryptions
I am trying to better understand the processes involved in e2ee using WebCrypto on the browser.
I understand that the only real method to use a passphrase to generate a symmetric key on the browser is ...
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Where is the AES key of ransomware stored (in the file header/trailer)?
Advanced types of Ransomware generate, usually, an AES 128 bit key (used to encrypt files, some types of ransomware use a unique AES key for each file). This key is generated on the fly. In addition, ...
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Is it possible to hack encrypted external HDD,if you have access to it? [duplicate]
If I lose my external HDD and somebody finds it and tries to hack, will he succeed?Is it possible to get data from encrypted disk by disassembling it and working with platters?
HDD is APFS AES 256 ...
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Is it safe to store data on APFS 256 AES encrypted external HDD disk?
I'm using a MacBook and want to store confidential data (financial documents, passwords, private photos, etc.) on an external HDD disk.
How safe is setting up APFS AES 256 encryption with disk ...
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Probability of getting different plaintext with different key
What is the probability that an AES encrypted file, using a wrong password, gets decrypted to something different than the plaintext, but which could still be likely to be interpreted an the true ...
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CryptoJS AES encryption/decryption problem
A simple encryption/decryption using CryptoJS gives me a weird output. Can anyone point me to where the code is wrong? (I'm looking for the output in the console)
var code = "Testcode";
var ...
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Is having a seperate server to handle encryption operations a secure way to protect a private key for a web application?
Assume I have two servers which are part of a production environment for a web application which handles sensitive user data. The first server is a ruby on rails application, and the second is a ...
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