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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What are the odds of brute-forcing an archive with 256-bit encryption?

I have a file (a stand-alone archive). I lost the password to it, but it has been encrypted using 256-bit encryption. The password is some 20-odd characters long (including non-alphanumeric ...
0
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1answer
35 views

My WCF application uses 2 way certificate message encryption - does it still need SSL?

I have a WCF service configured to use two-way certificate authentication on the messages. The server is also locked down through a firewall to only allow traffic from a single IP:Port that the ...
4
votes
1answer
349 views

How to implement client side encryption for CalDav & CardDav content?

I'm looking for a client-side encryption implementation that would be able to secure CardDav & CalDav data so that they couldn't be compromised even by the hosting provider. Server side: PHP or ...
10
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5answers
10k views

How secure is NTFS encryption?

How secure is the data in a encrypted NTFS folder on Windows (XP, 7)? (The encryption option under file|folder -> properties -> advanced -> encrypt.) If the user uses a decent password, can this ...
1
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1answer
91 views

Requiring 2 keys to access a content

I need to use an external service that can only be accessed by password. I don't like the idea of storing the plaintext password on the server, but AFAIK there's not much I can do. Considering this ...
1
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2answers
131 views

How to maintain security and trust with a PGP keypair for a team or group of people?

I've seen many instances where a company or organization generates and uses a PGP keypair for a team or group of people. Most likely they all have a copy of the private and public keys on their ...
2
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2answers
61 views

If I change my private key PGP passphrase, will the old private key+old passphrase work to decrypt already encrypted data?

Suppose I have a script that contains my PGP private key in plain text and requires me to manually type in the key passphrase to decrypt some data. Later, I decide that my passphrase is compromised ...
0
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1answer
196 views

Why the data in Aircraft's Black Box is Encrypted?

I have read somewhere that the Data in Air Craft Black Boxes are encrypted using various algorithm and only the manufacturers could gain access to the actual data of the BlackBoxe, Why the data in ...
2
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1answer
57 views

Is there a widely used protocol which builds on AES/GCM, and defines serialization formats of A, IV, C and T together?

note: Title edited to make the answer more useful to a wider audience I'm reading source code for encrypting files with AES GCM and see the following binary output. AdditionalAuthData IV ...
0
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1answer
38 views

Generate Passphrase from the data & encrypted data

right now I'm thinking about how to secure some data inside an Application... Now i have the following problem: Is it possible to generate the passpharase from a decrypted message and the same ...
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3answers
318 views

Would this kind of encryption be good at anything?

I have put much thought into this very simple algorithm and I have no clue if it was thought before... But I think it should have. I also know nothing about other encryption algorithms so I can't tell ...
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3answers
2k views

How secure is ionCube compiled code?

I use ionCube to keep the code I write concealed for my customers. If I would store a password inside the code and compile (not encrypt) it with ionCube encoder, would it be possible for a potential ...
0
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1answer
57 views

Review of approach to client-side only hashing and encryption for web application

Background: I have little knowledge of hashing and encryption, so please bear with me. I have posted a related question here: ...
5
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5answers
477 views

HOWTO : Email encryption in a browser

I have read about encryption and I think it's a good idea for me to encrypt my email. I run ubuntu 12.10 and use Firefox for browsing. In my quest for learning how to use gmail/hotmail to send and ...
0
votes
1answer
57 views

How do I identify a DES encryption key in a dump file using winhex?

I've created a C# program that encrypts and decrypts a file. The encryption method is DES. The program is exactly the same as in the following link, except that the part that removes the key from ...
0
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2answers
110 views

Best practice for sending IP Addresses

IP Addresses are pretty common around the internet so they're often easily found in plain text. However, let's say there's a number of IP addresses configured on a server to allow access through a ...
0
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0answers
26 views

Hash Based Encryption (fast & simple), how well would this compare to AES? [migrated]

First of all, I know it's a very bad idea to invent your own encryption algorithm. It's better to use existing known, trusted, extensively tested and studied algorithms with a proven track record. The ...
0
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0answers
14 views

Encryption using libsodium [migrated]

I have been struggling to encrypt/decrypt some data using crypto_secretbox_easy() in libsodium. I can't seem to find any good documentation on the usage. I want to get a password from the user, use ...
0
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1answer
58 views

Which mail clients support PGP/MIME - is there an overview? [closed]

Does anyone know if there is a current overview (I only found ones from before 2006) which MUAs (mail clients) do support PGP/MIME? I wonder whether there still exist issues like "Outlook Express ...
0
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1answer
119 views

Can I rely on encrypted cloud services like Mega? [closed]

The Mega site claims that all submitted files are encrypted upon upload and decrypted upon download, and at no moment have they any knowledge of the decrypted contents. (I assume others sites do it ...
0
votes
1answer
77 views

Data Protection act, who is liable? [closed]

Recently, a large UK shopping chain had the staff payroll database leaked (including bank details, all unencrypted) We've been told that we cannot take legal action and have so far been denied ...
0
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2answers
86 views

If P=NP, what is still cryptographically secure? [duplicate]

I know, I know - "If P=NP" is a really large, high-impact assumption. But this is a hypothetical. I mean, clearly RSA (and similar methods of obfuscation) would likely become totally irrelevant - or ...
4
votes
5answers
163 views

Can the wifi administrator in a shared office see mail sent through outlook?

I am hot desking in the same office as a potential competitor & would be using the same wifi. The building owner runs the competitor company. My question is, can the wifi administrator see mail I ...
2
votes
3answers
1k views

ECDSA vs ECDH vs Ed25519 vs Curve25519

Among the ECC algorithms available in openSSH (ECDH, ECDSA, Ed25519, Curve25519), which offers the best level of security, and (ideally) why?
0
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1answer
202 views

What happens if you run out of password attempts?

In Samsung Knox, you have 20 password attempts. However, it is never explained what happens if you run out of attempts. Does it delete your Knox data, do you need to enter the recovery PIN or is it ...
0
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2answers
98 views

gpg --encrypt fails

When trying to encrypt files, I get the following error in KGpg editor window: The encryption failed with error code 2 On the command line I get: $ gpg --list-keys /home/user/.gnupg/pubring.gpg ...
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0answers
79 views

Bouncy Castle C# API and NTRUEncrypt

I want to play around with NTRUEncrypt and I found this tweet that NTRUE is now part of bouncy castle. But I cannot find any proof of the existence in the source code of teh Bouncy Castle C# API, ...
1
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3answers
192 views

Is Salt, IV and Key necessary when encrypting password in a database using AES? If so, how should they be used?

Imagine I have a website with user accounts. I want to authenticate users, so I need to know if the password they provide matches the one stored in my database. To protect the passwords from prying ...
3
votes
1answer
314 views

GnuPG/KGpg Sign PGP Key - Sign User ID : What is the difference?

What is the difference between signing a user ID and a whole Key ? Which behavior is the best as to signing user IDs and Keys ? How and when to use "Local signatures" (non exportable) ? (I was told ...
12
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8answers
2k views

Is Steganography a safe method to store secret data?

I want to put some parts of my secret data into specific file with Steganography method. Is this method as safe as other encryption methods like RSA or SHA?
0
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2answers
196 views

Google's usage of RC4

I was reading about Google's usage of RC4 and an answer on stackexchange website stated the following: I know Google uses RC4 for most of its services, and this is the reason one shouldn't keep ...
1
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2answers
66 views

Using EncFS on a USB drive

I am using EncFS with a USB drive. How secure is this if my USB drive gets stolen? I ask because the .encfs6.xml file is saved in the USB drive and I can open it with a normal text editor. Do I ...
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1answer
84 views

MCRYPT_RIJNDAEL_256 max key allow? [closed]

maximun key for MCRYPT_RIJNDAEL_256 ? mcrypt_encrypt( MCRYPT_RIJNDAEL_256, <<==hash_hmac using sha512==>>, $text, MCRYPT_MODE_ECB, $iv ) Warning: mcrypt_encrypt(): Size of key is too large for ...
0
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1answer
83 views

What would be a valid approach to store private keys?

I'm implementing a mobile app which uses AES encryption algorithm to encrypt some critical values being sent to a remote server (basically, the user password), and then decrypted on the server side ...
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0answers
49 views

Why is the read write speed of a Protected DVD so slow?

I got a DVD with copy protection enabled on it, but the problem I am facing is that it loads extremely slow. I have seen such happenings with other kinds of protected DVD's as well. Can anyone tell ...
15
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3answers
399 views

Storing passwords in reversible form - a genuine use-case

What's wrong with you, you crazy fool, you're not supposed to be able to retrieve a password in plain text! I know. Hear me out. Assume I've got a service that's similar to Mint.com. For those that ...
14
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2answers
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How does non-ephemeral Diffie-Hellman key exchange become compromised in SSL when the RSA private key is leaked?

From my understanding, one of the major reasons we recommend Diffie-Hellman Ephemeral (e.g. DHE or ECDHE) over non-ephemeral DH, for SSL / TLS, is that compromise of the RSA private key (i.e. private ...
-1
votes
1answer
360 views

How do I find out what kind of encryption this is and how to decode it? [closed]

0xugm5chUcCO+KqKV58YwSwh3kMOHDFju8wtSIuZCbBAAFJaHkYDloRXz9qLEz3unGiAwZEyTvlRhnt6slOFZQ== Im wondering how to figure what this is and how to decrypt it.
4
votes
1answer
89 views

Why is it bad encrypt to with plain passwords as encryption key?

It's my understanding that using "normal" passwords, such as an easy to remember sentence, is bad practice. Is that because such a string will not be random enough, or something else? From Ruby's ...
3
votes
2answers
143 views

How does my bank knows my second and forth chars of my password

I see that the new login mechanism used by some banks in UK and also used by visa debit authentication is to ask for three random characters from your password at login (for example second, ninth and ...
1
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3answers
93 views

How encryption/decryption works when one generate random key?

I am new to this and want to ask a basic question.Suppose I used my password (say "ABC123") to generate a key using PBKDF2 algorithm (or any such algorithm).For encrypting a file I'll input my ...
0
votes
1answer
43 views

Are there software solutions take encrypted credit card data taken straight off a square credit card reader and insert them into a standard web form? [closed]

Does anyone know how you can take the encrypted output of a square card reader and insert it directly into a standard web form?
2
votes
1answer
77 views

Given a hash, salt, charset and password length, how do you get the password without brute-forcing it?

I got that question on an exercise and I'm not sure what to answer. Without conventional brute-forcing and without a rainbow table, how could I find out the password? An improved brute-force ...
19
votes
4answers
2k views

What are best practices to adhering to HIPAA encryption requirements?

As HIPAA's language is somewhat vague when it comes to actual technical requirements, what are best practices for PHI encryption for HIPAA compliance? I've seen varying levels at different ...
6
votes
8answers
2k views

How can I share files with other individuals using the cloud in a secure way?

I would like to use a dropbox because it is easy and convenient. But I want to encrypt the files with the public key of the intended recipient, so he will be the only one who can access the data in ...
2
votes
2answers
331 views

Are smart watches secure?

My Pebble smartwatch, like many (most?) other smart watches, uses Bluetooth Low Energy (Bluetooth Smart, BLE, BTLE, etc) to communicate with my smart phone. There's some security in the link, ...
1
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1answer
47 views

Root certifcate from an CA company which can be encrpyted by SoftHSM

Does anybody know a CA company which allows me to put the bought CA certficate inside SoftHSM (the same as an HSM but without any hardware, it is pure software)? Is it hard to work with the PKCS11 ...
3
votes
2answers
204 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 ...
1
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1answer
81 views

What does hardware full disk encryption imply?

I read the wikipedia article and few others, however I still don't have some things clear. The main question would be what does hardware full disk encryption imply for the user, however I have more ...
1
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0answers
47 views

Vigenere polyalphabetic cipher

A Vigenere polyalphabetic cipher has a repeated keyword length of k, and encrypts any of 26 letters using a rotation cipher. What is the keyspace of this cipher?