Encryption is the process of transforming plaintext using a cipher to make it unreadable to anyone except those possessing the key.

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Multiple email addresses connected to same PGP identity [duplicate]

I am setting up PGP (using GPGTools GPG Suite for OS X) and I use multiple email addresses daily. It appears I have several choices on how to do this, and I am wondering what is most secure/most ...
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Does a binary executable have to have some critical plain-text components?

When companies package binary executables, they are often encrypted, compressed, scrambled, and otherwise made so that your lazy hacker can't simply open the program up in Notepad++ and see the code. ...
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3answers
261 views

How To Prove That Client Side Javascript Is Secure?

Imagine that you have a web application that encrypts the user's data, such as a note or spreadsheet, on both the server and client. The normal process for a user using this web application is ...
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2answers
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Can I use SHA-512 hash as AES key?

I want to combine hashing and encryption for better security. So can I use a hash key generated from SHA-512 as a key in AES. For example, I have a password "secret", I calculate SHA-512 hash for it ...
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2answers
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NTAG216 lock bytes security [closed]

I want to ask about the "lock bytes" implemented on the NTAG216 by NXP. What exactly are these and how do they work? Are they a standard or is it some proprietary technology by NXP? Are there any ...
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1answer
331 views

Session Management for Private Key Passphrases in a Web Application

Use Case I would like to encrypt data in a database for a Web Application. The following requirements exist: Decryption should only be possible when a user provides a passphrase Encryption should ...
3
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1answer
181 views

What would be a simple example of an asymmetric encryption function (asymmetric function)?

I am trying to understand RSA encryption but the algorithm seems quite complex. I know that with asymmetric encryption you use a key and a function to encrypt data and a different function to decrypt ...
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15answers
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Why would someone “double encrypt”?

If I have a website or mobile app, that speaks to the server through a secured SSL/TLS connection (i.e. HTTPS), and also encrypt the messages sent and received in-between user and server on top of the ...
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6answers
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Compute the AES-encryption key given the plaintext and its ciphertext?

I'm tasked with creating database tables in Oracle which contain encrypted strings (i.e., the columns are RAW). The strings are encrypted by the application (using AES, 128-bit key) and stored in ...
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1answer
40 views

Potential FileVault problems in my setup

After FBI vs. Apple, I have a few questions about the security of my data. Here's my setup: AppleID is connected to local account I don't remember exactly, but I think I have selected option "Allow ...
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1answer
52 views

Key rotation for shared secret keys - recommendation

When using software that does encryption using shared secrets what are the recommended practices for changing the keys. To be specific, this is a distributed software running in a cluster and the ...
1
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0answers
96 views

How to enable ECDHE in openjdk-1.8.0 in CentOS 6.7?

I have seen many posts that hinted ECDHE is available in the SunEC provider way back in openjdk-1.6.0. My environment: CentOS 6.7 with openjdk 1.8.0.71-1.b15.el6_7. No ECDHE. Made 2 changes in ...
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2answers
103 views

Why does my private OpenPGP key look different between devices?

Something I noticed, when I use gpg --export-secret-keys -a on different computers: My private key looks different, even though they are the same key pair. Is that normal or does this indicate ...
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3answers
2k views

Flaw in encryption through pseudorandom number stream (from PGP documentation)

I was reading PGP docs and came upon a part written by Phil Zimmermann (PGP's creator) that piqued my curiosity: When I was in college in the early 70s, I devised what I believed was a brilliant ...
3
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2answers
479 views

Storing a user's password in a retrievable manner

I currently store my users passwords as PBKDF2 hashes, for the authentication part of my web application. Each user also has their own private key and public key (also stored in their user profile in ...
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3answers
103 views

What is the benefit of adding data encrypting key then store it (encrypted) along with data

To protect user's sensitive data, I am considering the following 2 approaches: Create 1 data encrypting key (DEK) for each user, use it to encrypt (using AES CBC mode with a random IV for each ...
0
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2answers
257 views

Why does Telegram not use end-to-end encryption? [closed]

Signal and Telegram are both mobile applications that "try" to ensure secure chats. Signal uses end-to-end encryption, Telegram does this as well (in 'secret chats') but it does not use end-to-end ...
3
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1answer
101 views

What happens when encrypted email is in-transit?

If you're using a service that offers end-to-end encryption, what happens when you send an email to another non-encrypted email address? Let's say I write my email in ProtonMail and then send it to a ...
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3answers
2k views

Why can't the FBI copy the contents of an iPhone they are trying to crack?

Making the news rounds now is a story about the courts ordering Apple to disable the automatic deletion of data after 10 failed password guesses. What I don't understand is, why doesn't the FBI just ...
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6answers
16k views

How to properly encrypt a communication channel between a client and a server (without SSL)?

I have a poor knowledge in the world of cryptography, I'm just starting to learn it so I'm a newbie :) As a project for getting into the field of cryptography I want to write a client\server program ...
2
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2answers
37 views

Could I use a TimeStamp also as IV?

For an academic application, I use AES-GCM to encrypt my frames between 2 parties. To enhance security, and reduce the possibility of replay, I'd like to use a TimeStamp in my frame exchanges. But, ...
13
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2answers
640 views

Is there a cipher suite “translator”

I have a list of cipher suites in this format: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384_P384 Is there a fast, easy way of translating it to more human readable/management readable format? :)
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3answers
157 views

How to decrypt a file encrypted under multiple public keys GPG

According to https://www.gnupg.org/gph/en/manual/x110.html To decrypt a message the option --decrypt is used. You need the private key to which the message was encrypted. Similar to the ...
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7answers
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How can I decode a message that was encrypted with a one-time pad?

How can I decrypt a message that was encrypted with a one-time pad? Would I need to get that pad, and then reverse the process? I'm confused here.
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2answers
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Encryption: Files that can't be encrypted/cryptolocker family doesn't encrypt?

Are there any type of file whatsoever that can -not- be encrypted? Is there any data that can't be encrypted by the regular RSA encryption methods? Also, does anyone know what files the cryptolocker ...
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3answers
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openssl: recover key and IV by passphrase

A large amount of files were encrypted by openssl enc -aes-256-cbc -pass pass:MYPASSWORD Openssl should derive key+IV from passphrase. I'd like to know key+IV equivalent of that MYPASSWORD. Is ...
3
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1answer
85 views

How does ProtonMail manage search?

There is a service called ProtonMail that encrypts email on the client, stores encrypted messages on their server and sends it encrypted in some fashion (depending on what email service the recipient ...
5
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1answer
184 views

Which block cipher for a very short (40-bit) message?

Question: I'm trying to encrypt a 32-bit message to produce a ciphertext no longer than 40 bits. Are there vetted block ciphers or other good ways to encrypt very short messages? Are there any ...
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2answers
59 views

Does Thunderbird Enigmail plugin decrypt attached files?

From my research I have found out that you can easily send encrypted messages to one another using Enigmail. If first I encrypted a file,then attached it to an email, sending it through Enigmail to a ...
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1answer
70 views

Tool for reading application data before it's encrypted [closed]

For a test, I have a simple client-server Python socket-based application with a self-signed certificate. The code is copied from here. Although I don't see the traffic as TLS in Wireshark (why?), ...
3
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1answer
98 views

uploading pkcs12 to yubikey piv slot

i have a id_rsa (private key which is used by me to authentication and encryption together with cert on yubikey piv smardcart provider on slot 9a) now i wish to use this key to create a pkcs12 ...
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1answer
96 views

Is storing encrypted and hashed versions of the same data less secure?

I have some database columns which are encrypted. Obviously there is no way to filter these by plaintext value. As the data stored in the db is ~~salted~~ combined with the IV, there is no way to ...
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2answers
101 views

Is email sent form a Java web-app over a HTTPS connection encrypted?

I'm working on a Java web-application which runs on a HTTPS connection. This application sends emails to its users. I want to protect those emails from man-in-the-middle attacks and other potential ...
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5answers
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3answers
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Why can't apple simply add the backdoor now and then remove it after the FBI is done?

Summary of the current situation by @TTT Apple released an open letter to the public outlining their reasons for not complying with the FBI's demands to modify the iPhone's security mechanism. ...
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5answers
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SHA, RSA and the relation between them

SHA is the hashing mechanism. However, RSA is the encryption algorithm. So does RSA algorithm use SHA hashing mechanism to generate hashing keys which in turn is used to encrypt the message?? ...
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27 views

Finding the key of encrypted string (given known decrypted message) [duplicate]

I have a bunch of messages where I can run the encrypted message against a validation services, and get a response that the encrypted message is valid as well as the contents of the encrypted message. ...
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3answers
4k views

How To Recover EFS Cert From Backup?

I made a backup of the old Win 7 Pro then did a clean install. But I forgot to export my EFS encryption certificate, so when after I restored the encrypted files from backup I could no longer access ...
6
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2answers
363 views

Am I weakening symmetric OpenPGP encryption by deploying a custom pre-derivation?

I often use GnuPG to encrypt files with a passphrase. I'm very paranoid, and afraid that the key derivation used by GnuPG isn't slow enough. For this reason, I've decided to do my own key derivation ...
3
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1answer
55 views

How to prevent data from Interception?

I am a web developer. A few days ago, I used Burp, to intercept facebook's official App over network, by setting up proxy. I noticed that the data was encrypted. While I have been using Json to ...
1
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1answer
374 views

Can I decrypt a DiskCryptor-encrypted hard drive using Veracrypt?

I have a hardrive I encrypted with DiskCryptor back when I was using Windows. Now that I have Linux I want to decrypt the hard drive but it turned out DiskCryptor is not available for Linux, whereas ...
3
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1answer
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Encrypting data within SQLite database in Java - How to store key?

So, a bit of context before I start may be handy. I am developing a Java desktop application which will use an SQLite database to store/process data. The application will utilize authentication to ...
5
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2answers
7k views

Perfectly secure Postfix MTA (SMTP) configuration

I want to secure my root server (further) service by service, starting with the SMTP service (Postfix MTA) as the most busy one. I the course of setting everything up, I read a lot about security and ...
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5answers
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Is 7-Zip's AES encryption just as secure as TrueCrypt's version?

The main difference being TrueCrypt creates containers and 7-Zip encrypts the file itself, so file sizes can be guessed. Now let's just talk about the strength and breakability of the encryption. ...
3
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2answers
45 views

Specifying my key name while encrypting file to some receiver using GnuPG

I would like to make sure of one thing. When I am encrypting file, the only needed key to specify is --recipient, because I only need to specify key to encrypt (receiver key)? I don't need to specify ...
23
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3answers
46k views

Secure Configuration of Ciphers/MACs/Kex available in SSH

Following on the heels of the previously posted question here, Taxonomy of Ciphers/MACs/Kex available in SSH?, I need some help to obtain the following design goals: Disable any 96-bit HMAC ...
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Is C a good choice for security-related software any longer? [closed]

C is a rock-solid and widespread programming language that is very popular especially in the FOSS community. Many security-related software (such as encryption libraries) are written in C and will ...
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1answer
47 views

Location/proximity based decryption using separate machine

I read a long thread where the whole issue was revolving around deriving decryption keys from GPS location. This has huge issues, as being present at a location is not needed to know the location. ...
4
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1answer
219 views

decrypt a string with a password, but unknown method

I want to run through multiple algorithms against an encrypted string. I have the password and the encrypted string but not the method it was encrypted under? what would be the best method to find ...
22
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5answers
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Multi-boot with full hard drive encryption and pre-boot authentication

How would I set up a multiboot system which supports full hard drive encryption and pre-boot authentication. I have a system with Ubuntu, Windows 7, Windows XP, and I would like to install Red Hat. ...