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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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How should I share the key of the AES algorithm in each client?

My doubt would be the following: How should each client know the encryption key? Using the AES algorithm. (or the best way): Save it in a file encrypted by password? Save it in a DB? Send it over ...
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How to decrypt an openssl_encrypt() encrypted value using MySQL query? [on hold]

If I am using the following php script to encrypt a field in my database: <?php require_once('../api.php'); $newApi = new api(); $conn = $newApi->connection(); //$key previously generated ...
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0answers
40 views

Fix use of hardCoded Cryptographic key

I have a method that obtains the secret key to be able to encrypt with AES.The secret key is stored in database. As seen in the method, I use a Stored procedure to get the secret key value and assign ...
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1answer
93 views

is AES-128-CBC already broken?

I just want to know if AES-128-CBC is secure enough to use in an OPENVPN,I asked and they told me AES-128-CBC is completely broken and is considered a weak encryption. is it so?
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Can I use RSA to encrypt an AES256 key that I put at the beginning of my AES256 encrypted file?

I have a master server generating large files for other (known) servers to download. Those files: Are quite big. From 20MB to 5GB. Are written once by the server and then it forgets about them. ...
2
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1answer
98 views

AES/Rijndael Encryption Does block size matter for security?

Would AES with a 256-bit block size be more secure than a 128-bit block size? I'm curious if block size really makes something more secure. I'm dealing with a third party to use their API and they ...
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1answer
97 views

AES Encryption is this overcomplicated encryption?

I'm working with a vendor's API and it recommends the following steps for transmitting an encrypted value: 1) Convert the encryption password to a byte array. 2) Convert the value to be ...
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4answers
296 views

Can I use a user's password hash as the AES key to make a one time token?

I want to make a one time token that users use to reset their password. The token should be invalidated once it is used, is it safe to use their currently hashed password as the aes key to encrypt the ...
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5answers
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Can I recover a lost AES key?

I had encrypted 2 MySQL databases with AES_ENCRYPT in ECB 128 bit mode. Now I forgot my encryption key, but I have plain text (I have one database without encryption and same with encryption). How to ...
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1answer
43 views

Is there any 'Open Enrypted File Container' Format?

Tools that create 'encrypted file containers' use open encryption standards like AES to encrypt container contents, however the container format is proprietary, I am guessing, so need the same tool to ...
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2answers
41 views

Understand aes cbc IV

When I use AES CBC, the encrypt function needs to get an input-buffer to encrypt + key + IV? Is IV like one more key, or IV is generated by the key (so the encrypt function only needs to get the ...
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1answer
35 views

Potential security issue with md5 filename

I've been storing files using a filename of the md5 hash of the file. This allows me to not store duplicates of the same file and avoids any filename clashes. Each file has uses a different salt/iv. ...
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1answer
49 views

How to use login details to make a key for AES encryption and decryption

I have recently starting looking into AES encryption for a side project. I am researching this till now so if there is something wrong about my concept please correct it. According to me If i want to ...
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1answer
63 views

Decrypt AES 128 CTR with the IVs (counter) but not the key

I have the encrypted files, the random IV for each encrypted files and the counter increment function but I miss the key. Is there anyway for me to decrypt the files?
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0answers
64 views

Help me understand Encryptpad and 7-zip for encryption

I was looking to encrypt some text files (containing sensitive data) so I could safely keep them online (e.g. Google drive). I have found three options: 7-zip, which does AES-256 Encryptpad, which ...
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1answer
92 views

OpenSSL: what's the difference between -kfile and -pass?

It seems both -kfile and -pass can be used to encrypt files with a 2048 bit keyfile? I don't understand the difference between the two methods: $ openssl enc -salt -aes-256-cbc -in inputfile.txt -...
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2answers
497 views

The way to determine IV for AES encryption, possible security problems with this approach

I am trying to make a folder encryption with maximum automation (except password input). Inside a bash script I do the following: echo $RANDOM | md5sum | cut -d' ' -f1 > iv and then using it: ...
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1answer
43 views

Ensuring key integrity

I have encrypted AES key stored in the database with the encrypted data. AES key is encrypted with a key derived from the passphrase. I want to ensure the integrity of the stored AES key. Is the ...
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1answer
69 views

Is AES+hash rather than HMAC problematic?

I will now ask a strange question, but bear with me. I can't share the entire usecase, but the point is to allow the holder of a secret key to create "strings" (used in other systems). The strings ...
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2answers
160 views

AES-256 decryption after key destruction. Possible or not?

Can AES-256 be decrypted if after the encryption process you destroy the key that must be used to decrypt the data, is it possible?
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1answer
66 views

Advantages of encrypting IV in AES GCM

I've got a friend who stores some important data locally in a database. Before storing, he however first encrypts it with AES GCM with a certain key. He then encrypts the IV with another key, and then ...
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2answers
171 views

Does using AES-256 encryption really grant any further security?

AES-256, as far as I know, generates an 256 bit key to encrypt a message, and the 256-bit key is generated by a known algorithm starting from the password the user chooses. Since the encryption is ...
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1answer
93 views

Is AES + MAC more secure than encrypting plaintext along with its hash

Suppose I want to encrypt some plaintext and I can only use an unauthenticated AES mode like CBC. One way of adding authentication is encrypt-then-MAC, where the two different keys for AES and MAC ...
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1answer
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What exactly is unsafe in using openssl AES with a password? [duplicate]

An answer about AES encryption starts with a disclaimer: Please note: You can use this to hide birthday-gift-ideas.txt from your roommate, but don't expect it to be secure against a determined ...
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1answer
109 views

Using AES encryption to generate MAC (and provide authentication/integrity)

Ignoring that there are far better and more standard approaches to providing authentication and integrity guarantees, what (if any) weaknesses would a system as outlined below that relies on AES (AES/...
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0answers
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Why is MySQL 8.0 AES_ENCODE unsafe for statement-based replication?

I read this interesting note in the MySQL 8.0 documentation that seemed a bit confusing to me: Statements that use AES_ENCRYPT() or AES_DECRYPT() are unsafe for statement-based replication. As I ...
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1answer
84 views

Storing RSA private/public key pairs in a file, on linux

Would it be wise to: Generate a lot of priv./pub. key pairs, and store them in a file on the server machine(Linux). (Let's say in a companies server room) Then encrypt the file with AES, and store ...
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2answers
178 views

Is AES easier to crack when the input is small? [closed]

Say you just want to encrypt a number. For example, say the number could be any double. A double in C# and Java is 8 bytes. If you were to encrypt a double using AES: var cypherText = AES.Encrypt(...
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1answer
26 views

How harmfull might be predictable bytes when using AES-CTR

I use AES-CTR to perform on the fly encryption of packets. Each packet is 16 bytes long, however, depending on what is being transferred, the 16 bytes may not be used. So far, unused bytes are left to ...
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0answers
49 views

Microsoft Cryptographic Service Providers

I have a few questions about Microsoft's Cryptographic Service Providers. I am creating an AES encryption method whose key is encrypted using the RSA. I am trying to figure out a way to store the RSA ...
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0answers
35 views

What is this key management scheme called

We are building a system, where the messages between services is encrypted with Data Encryption Key (DEK). The DEK is attached to the message, but encrypted with another key, Key Encryption Key (KEK)....
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0answers
32 views

User specific AES-256 key for file. Retroactive encryption

I may be falling into a classic encryption-problem trap here... I've been developing applications using AES and public/private key encryption for some time so I have a good understanding of straight ...
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1answer
102 views

Is it possible to encrypt a file using both AES-256 cipher, password and keyfile using OpenSSL?

Is it possible to encrypt a file using both AES-256 cipher, password and keyfile using OpenSSL? I want to encrypt a file using OpenSSL. After hours of testing I have found a command which may ...
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0answers
86 views

Javascript asymmetric password-based encryption

I want to code a web app that allows 2 users to send encrypted messages to each other, and I want to maximize security, so I want to minimize the amount of trust I put in my cloud provider (both the ...
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0answers
38 views

WPA2 IV all zero in EAPOL message of 1,2 and 4

While we know that in the best practice in any AES communication is to not use a constant or all zero IV. However, when I capture my authentication progress between my STA and AP. I found out that ...
2
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1answer
61 views

Is there any need for PBKDF2 with AES when using a uniform key space?

I'm looking at some code that encrypts data in a database using AES. Before doing so, the encryption key is passed through a PBKDF2 function. Reading up on this, it appears this is for when the key ...
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1answer
147 views

OpenSSL how to get the speed od AES-128 from the results I got

so first what do these values stand for are they cycles per 3 seconds? and can I how can I get the speed from these results for AES-128 ? $pi@raspberrypi:~/iot_c3 $ openssl speed aes-128-cbc Doing ...
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2answers
166 views

Is it safe to encrypt my password with the password itself?

I'm using a password to encrypt some data. However, upon decrypting, I want to check if the entered password is correct. In order to do so I encrypt the password itself. Then upon decrypting, I check ...
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1answer
512 views

Where to store AES keys when encrypting files at rest?

I've gone through the below question: How to store an AES Key? an Initialization Vector(IV)? And read the below articles about how to encrypt files using AES in CBC mode: http://www.novixys.com/...
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2answers
827 views

MySQL AES_ENCRYPT string key length

In MySQL there are builtin AES_ENCRYPT() and AES_DECRYPT() functions which take the form of: AES_ENCRYPT(str, key_str) What length is required for the key_str argument? Can it be variable? What is ...
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4answers
296 views

Common format to send encrypted data + IV?

I have an app that receive data from third parties using various protocols: MQTT, HTTP, AMQP, ... Some clients cannot use TLS (iot devices without TLS support), so we need to find some compact and ...
2
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2answers
190 views

Should a password based AES CBC encrypted string have extra security?

For a Java application that I wrote, I take a password provided by a user and generate a 128-bit AES key from it using 100,000 iterations of PBKDF2-HMAC-SHA512 with a randomly generated 512-bit salt. ...
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0answers
66 views

Bluetooth low energy encryption using chacha20-poly1305

The BLE data is encrypted using AES-CCM. the TLS1.3 removed AES-CCM from the cipher-suits due to security issue. My question : why don't they encrypt the BLE using chacha20-poly1205 ? is it because ...
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2answers
112 views

Help to review 2FA algorithm

First of all, I know, don't reinvent the wheel... But there's a good reason for this. So I have been implementing a generic 2 factor authentication code generation/validation algorithm in order to re-...
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1answer
357 views

AES successful decryption using wrong secret key

I have a problem with AES encryption. I need to encrypt plaintext using CTR with a random IV. Then I need to encrypt the IV with the same key. I know that it is not required to encrypt the IV, but I ...
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1answer
4k views

How can I use openssl to decrypt AES-encrypted data using the key and initialization vector?

I am attempting to follow the example in this question: Where is the salt on the OpenSSL AES encryption? but I'm having some trouble decrypting using the key and initialization vector. When I ...
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0answers
170 views

How to recover forgotten AES-256 password with bruce force?

The password was set on a flash drive using LaCie Private-Public for Windows 10. The password is 12 character long. For each character, I know if it is a number, special character, lower case letter ...
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1answer
485 views

Is CBC mode for AES still safe to use in 2018?

I'm using AES-256 CBC mode in C# to encrypt various amounts of texts. The key and IV are always generated properly randomly. However, would GCM mode provide any noticeable security gains over CBC?
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1answer
239 views

Providing data integrity with AES

A question for an exam asks me to provide data integrity of a file F with AES and a shared secret key between Alice and Bob, if there is a way. The message is sent by Alice to Bob. I thought of the ...
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1answer
182 views

TLS1.2 AES 128 CBC Encrypted Data size

I know that TLS ciphers such as TLS_RSA_WITH_AES_128_CBC_SHA transmit data as shown. From my understanding, the ciphertext must be a multiple of the block size, which in this case is 16 bytes. However,...