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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For users that does not use PGP, what would be the other channel to securely send them a document?

I would like to send a document that is confidential to users that have no clue what PGP is (so no point in teaching them how to install it etc...) via email. The real question is how to do that? ...
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4answers
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What are you doing when you move your mouse randomly during a truecrypt volume creation?

Is that called a 'round' every time you move your mouse when creating a new volume? I'm talking about the screen with the random numbers during the volume creation process. What is the purpose of ...
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2answers
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What's the difference between a hashed and an encrypted password?

Alright, so I know this may sound dumb, but I'm having a hard time understanding what an encryption would be since it's different from a hash. I've read up on it, but I'm still not quite sure. So, I ...
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6answers
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How are ProtonMail keys distributed?

There is a service called ProtonMail. It encrypts email on the client side, stores encrypted message on their servers, and then the recipient decrypts it, also on the client side and the system ...
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4answers
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Does symmetric encryption provide data integrity?

Let's say I have one server that encrypts a file with a symmetric key, e.g. AES-CBC, and sends it to clients that decrypt it. Does that provide data integrity when decrypted? Or is it possible for ...
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Has cryptography reached the development level where social engineering is the only reliable method of attack?

Note that for the purpose of this question, "social engineering" means extracting information from humans, be your methods compliant with Geneva Conventions or not. Simply put: Do cryptographic ...
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3answers
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Can I use a private key as a public key and vice versa?

I have code to encrypt data using a public key and decrypt it using a private key. This is useful when a client wants to send data to a server and know that only the server can decrypt it. But say I ...
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start point into cryptography and encryption [closed]

Recently I am growing passion for security/encryption/cryptography. I follow some famous people in this domain on twitter and read articles over the web. However, this topic seems deep and every time ...
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6answers
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Why not RSA-encrypt the entire document?

I have recently learned of a way for person B to verify that a document sent from person A is indeed from person A. Person A gives Person B his public RSA key. This must be done reliably. Person A ...
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1answer
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Which Cryptography algorithm is used in WhatsApp end-to-end security?

I have a presentation to make on Social Network Security. I have been doing some research regarding this. I did a lot of searching, but was unable to find the Crypto Algorithm used by WhatsApp for ...
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3answers
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Is amazon S3 secure enough to hold personal documents?

I have a client who is looking to hold personal information such as Driving Licences and Insurance documents in order to verify if a user of the site is who they say they are and lives where they say ...
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6answers
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Why encrypt data in memory?

I saw that KeePass not only encrypts its password-database-file, it also can encrypt the passwords it holds in memory. This is just an example. I thinking of a new project dealing with sensitve / ...
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Primary Key as Salt?

Is it okay to use the primary key as the salt in a Users table? The only disadvantage that I can see is if the PK changes (unlikely), then the passwords break. What are your thoughts?
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5answers
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Is there a digital “safety deposit box” equivalent?

Digital safety deposit boxes: do they exist? if yes, are (any|they) trustworthy? There are many bricks and mortar financial institutions where one can rent a locked box in a locked room and be ...
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3answers
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Using TPM with DMcrypt?

Is it possible to use TPM for storage of some private key? It's not a full-disk encryption , I want it to be compatible with existing LUKS, just add another key, and store it in the TPM.
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4answers
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Database Encryption Security

I am encrypting and decrypting my database data from my web applications API. If my web server is compromised, what is to keep someone from using that same method to retrieve the data? For example, ...
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3answers
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How do I ensure data encryption on Samba transmission on *NIX systems?

I have a heterogeneous system (both MS and *nix) that communicates with CIFS/SMB. How can I ensure proper data encryption at the application layer?
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1answer
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When authenticating ciphertexts, what should be HMACed?

Some have argued for using AES-256-CTR with HMAC-SHA-256 for authenticated encryption over AEAD-specific modes like EAX and GCM. However, when doing, this, what should be HMAC'd? And how? ...
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4answers
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Is Steganography considered encryption and subject to USA export restrictions?

I have written an application for Apple's iOS which embeds messages in JPEG files using steganography (see http://en.wikipedia.org/wiki/Steganography). For the purposes of this question lets assume ...
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2answers
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How would I implement “Broadcast Encryption”?

I have a stream that I want to encrypt for broadcast to 10,000 subscribers. I know I should encrypt this data using a symmetric key; and also intend that this symmetric key will be rotated every 30 ...
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2answers
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Can a Firefox add-on or plug-in access the user's websites' saved passwords in decrypted mode?

Going deeper into the previous question on Firefox plugins and add-ons malware risks: Could a Firefox add-on potentially decode and capture the encrypted websites' passwords saved in the browser?
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Encrypting files in a windows environment

We have certain client data which must be encrypted at all times. The part we have been struggling with is encrypting files on network shares. Currently we have network folders encrypted using PGP ...
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1answer
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GPG-encrypted mailing list and other approaches to safe communication

What is the best way to communicate privately on a mailing-list? Requiring each member of the list to have the public key of each other member, and encrypt their messages with those, is cumbersome to ...
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Storing sensitive information securely

I know there have been a few questions about this already, but I just wanted to know if anyone can take a look at my design plans to see if there are any gaping security holes. I am in the process of ...
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3answers
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Best practices on securely storing access tokens

What would be the best practices for storing access tokens of another api for your users? In particular I'm developing an application with some friends that let's user log into Facebook to both ...
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1answer
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How would one verify that the public key from WhatsApp's servers belongs to the person I expect it to?

WhatsApp had recently announced end-to-end encryption on all communications. While that's an impressive move, I still have a big open question mark. The articles and this white paper suggest that the ...
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3answers
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Trying to understand why signatures in root certs “are not used”?

Taken from here: Don't worry if the root certificate uses SHA1; signatures on roots are not used (and Chrome won't warn about them. Why are the signatures not used? Are not root certificates ...
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Why does IV not need to be secret in AES CBC encryption?

According to Wikipedia, the initialization vector (IV) does not have to be secret, when using the CBC mode of operation. Here is the schema of CBC encryption (also from Wikipedia): What if I ...
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4answers
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Why does PGP use symmetric encryption and RSA?

Looking into the details of Pretty Good Privacy, I'm confused as to the reasoning behind encrypting the message with a session key and the key with the recipient's public key via RSA. I fail to see ...
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3answers
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Is multiple encryption a good idea?

I know that many encryption algorithms, while secure, have vulnerabilities. To reduce risks, would multiple encryption like this Blowfish_CbC ( Rc2_OFB ( AES128_CBC (myfilecontent))) be a good ...
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Identity-Based Encryption - how secure is it?

I was always taught never to invent my own crypto algorithm, and never to trust someone who has a proprietary algorithm. I'm looking at Voltage SecureMail, which uses IBE (identity-based encryption) ...
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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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6answers
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What does “key with length of x bits” mean?

I'd like to know what it means to say "the cryptosystem C uses keys with a length of x bits". I do not understand what the bits length means... doesn't it depend on the encoding? The same word encodes ...
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At what point does adding more iterations to PBKDF2 provide no extra security?

If my true passphrase is used only to generate a hash which is used as the cipher's actual key, doesn't that mean it's possible to try and brute force the cipher itself? I know it would take an ...
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1answer
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PayPal encrypted with obsolete cryptography

My Chrome just complained from PayPal's security, similarly to this issue: Google Chrome "Your connection to website is encrypted with obsolete cryptography" The identity is verified, but ...
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TrueCrypt vs BitLocker

I would like to ask which one of these TrueCrypt or BitLocker is safer to implement and encrypt the data in a small business environment (Windows 7, 8.1 and Windows Server 2012r) I read about ...
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3answers
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Choosing a session ID algorithm for a client-server relationship

I am developing an application which has a client-server relationship, and I am having trouble deciding on the algorithm by which the session identifier is determined. My goal is to restrict ...
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5answers
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Use RSA keypair for PGP encryption and decryption

Is there a way that I can use a RSA keypair with PGP? What I mean is that I have 2048 length keypair and i want to use that to encrypt and decrypt data. But all I have found is that the PGP uses some ...
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7answers
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Why can an encrypted private key be brute forced?

When using SSH keys to authenticate to a server for remote access, why is it possible to devise the true key and therefore the passphrase from an encrypted private key, without checking each guess of ...
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2answers
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Is a large number of RSA-encrypted files a vulnerability?

Would having a large number (10^4) of RSA encrypted files make it easier for an attacker to find my private RSA key? Update: These files would be available to the attacker, and perhaps the content of ...
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When using AES and CBC, can the IV be a hash of the plaintext?

[Originally on programmers.stackexchange.com with title: Can you encrypt with AES+CBC and search the encrypted data] Basically, I'm going to go with Advanced Encryption Standard with either ...
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How (in)secure is POP/IMAP/SMTP

I'm making a few assumptions about basic email security, and I want to confirm or clarify some of these points to make sure I understand the big picture. Please correct me where I'm mistaken: The ...
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2answers
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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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How is 4G LTE encrypted?

After a few quick searches for 3G security I was able to learn that this standard uses the KASUMI block cipher, of which several weaknesses have been identified (although apparently none of practical ...
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Smartphone / GSM Sniffer

This question would be in the category of SmartPhone Sniffers. So we have sniffers that can show the packets that are being sent across a wired or wireless (802.11) network. I am just performing a ...
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3answers
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Can I use the same password both for SRP and for client-side encryption?

Suppose a less-than-trusted server is used to store users' confidential data (encrypted at the client side), and both tasks - authentication and encryption/decryption - should be doable with a single ...
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1answer
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Where is the salt on the OpenSSL AES encryption?

I'm interested in knowing how and where OpenSSL inserts the generated salt on an AES encrypted data. Why? Im encrypting data in Java classes and need to guarantee that I can use OpenSSL to decrypt ...
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Is it possible to prevent a physical attack on full disk encryption?

I've been researching into some methods to ensure that disk encryption keys can't be stolen, and one that I've come across is called TRESOR. With this kernel patch, you can create a partition that is ...
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Is Windows BitLocker secure?

Naturally I feel that I have to ask this question, since it's a built-in feature in Windows. Let's say someone has physical access to my PC, is there an easy way for them to access a BitLocker ...
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Is it possible to use S/MIME in the web client of Gmail?

I could not find any options in the web interface of Gmail. All I could find was a Firefox plugin to use S/MIME with Gmail, but it seems to be outdated.