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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Can I use hardware random number generation on my computer? Am I already using it?

A lot of computer security depends on encryption: SSL connections, TCP packet sequencing, encrypted files, etc. These depend on random number generation to ensure that attackers can't guess the ...
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How can i find what hashing algorithm was used?

One of my clients has asked me to modify the login page that their board members use to access their materials. The problem here is that the person previously responsible for this has left no ...
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Who tells that TrueCrypt is secure?

Assuming you're not running on a compromised machine and you're following common recommendations (long random passwords, etc.), who specifically (name and affiliation) asserts that TrueCrypt is ...
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How can I determine the encryption strength of an SSL connection

If I've connected to a https url, how can I determine the cipher strength of the connection? My understanding is that after the asymmetric public-key handshake the information is encrypted using a ...
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392 views

Encrypting a disk that has stuff on it?

Ok, so a pretty big disk ~1-2TB (90% full, multiple partitions + 2 operating systems on it), needs to be encrypted and zeroed-out, and it's a bit too much data for backing it all up before encryption. ...
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379 views

What can one do when encryption methods fail?

I'm in search of an expert to answer my curiosity. Suppose that methods like AES/DES, SSH, PGP, RSA, etc. can be cracked or fail somehow. In other words, suppose that it's possible to determine one ...
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What common products use Public-key cryptography?

I want know what common use products are there that use public key/private key cryptography?
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What is the DUKPT Key Derivation Function?

I'm tasked with decrypting ciphertext acquired from an encrypted card reader. The card reader utilizes DUKPT(derived unique key per transaction) scheme and 3DES encryption. I don't have a problem with ...
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Is using HMAC to transmit a password OK?

I'm writing a small webapp and I don't want to transmit login passwords as cleartext. As I don't have SSL available I've written a one-time challenge system which sends a random string with the login ...
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What Partial Homomorphic Encryption implementations exist and how do I leverage them?

It appears that only Partial Homomorphic Encryption(P.H.E.) is practical for modern day (2011) use. However I'm having difficulty locating libraries (FOSS or otherwise) that enable me to leverage ...
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Securing a laptop against attacks (article)

I came across this article when looking for ways of hardening my laptop, and this guide seemed extremely thorough. It is perhaps overly paranoid, but it will be good to have a guide I can trust should ...
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Why do so many embedded devices use shared keys?

Many commercially available embedded device manufactures use the same keys for all instances of their respective devices. This situation is so rampant, a project called littleblackbox has created a ...
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Automated encryption detection

Is there any program that, given a cipher text, it would tell me what the encryption algorithm is? What if I have the plain text? Is there something that can be done in that case?
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moving from MD5 to SHA-512

This question is more of a security policy than a technical security question. Many years ago I developed an asp.net site, implemented Forms Authentication, and stored the user passwords as MD5 ...
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577 views

Most widespread use of PGP after 20 years

Phil Zimmerman released PGP (Pretty Good Privacy) on June 5, 1991. As we examine the legacy of that far-sighted and brave act 20 years later, what are the most widespread and helpful uses of PGP ...
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536 views

Reason for writing Self-Decrypting Virus

What is the rationale behind writing a self-decrypting virus? By this I mean a virus that has it's payload encrypted, decrypts at runtime and runs it. How does this protect the virus from antivirus ...
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728 views

Is ECDSA breakable by quantum computers?

Is ECDSA secure from quantum computers? Will quantum computers be able to calculate it's private keys from the knowledge of the public key once there are working quantum computers?
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Security of email [duplicate]

Possible Duplicate: How commonly are SSL/TLS or S/MIME used by e-mail providers? Say, Alice uses gmail and Bob uses hotmail. Alice wants to send an email to Bob. Alice goes to gmail ...
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3k views

Is 1024bit Diffie Hellman key exchange secure?

My system uses AES-256, 4096bit RSA CA key and 2048bit RSA keys for servers together with SHA-256 signing. Does using 1024bit DH key exchange lower its security? I read on one mailing list that ...
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628 views

How does a weakness in a random number generator lead to a compromise of the entire cryptographic process?

In the news, there are several articles (here, here, and the technical point of view) which have to do with a weakness in a random number generator. The question is somewhat twofold. What symptoms do ...
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640 views

How practical/important is the Lucky Thirteen TLS attack?

I was reading this article which talks about a new attack against TLS being called Lucky Thirteen. It claims to allow repeatable MitM attacks against HTTPS connections. It's described as being fairly ...
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When using AES and CBC, is it necessary to keep the IV secret?

If I encrypt some data with a randomly generated Key and Initialization Vector, then store all three pieces of information in the same table row; is it necessary to encrypt the IV as well as the Key? ...
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1answer
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How does adding a random serial number improve a certificates' security?

This article says: "Finding collisions is a tricky process, since it requires you to muck with the bits of the public key embedded in the certificate (see this paper for more details). Also, ...
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1answer
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How to study the packets sent by a keylogger

One of my friends runescape account got hacked through key-logger. He downloaded a runescape gold generator from a file sharing site and tried to use it. I have a strong doubt that it is a key-logger. ...
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Security implications of storing the password hash along an encrypted AES key

I am using the PKCS#5 standard to generate a key using a random and unique salt and the user's password in input. Consider this key as the "encryption" key. The "encryption" key is used to encrypt a ...
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Location to store an encryption key

I'm building a secure system which stores messages on a server in a Postgresql database. The messages are stored encrypted with PHP's openssl_encrypt() function with the AES-256-CBC method. At the ...
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1answer
562 views

Why can't I use the same key for encryption and MAC?

I wrote a simple file encryption program as an example of how to do encryption correctly, but after reading a questions about encryption + MAC, I think I made a mistake by using the same key for both. ...
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571 views

Do honeywords add any real security?

This paper proposes the concept of honeywords for detecting if a password database has been compromised. As far as I understand it works like this: You save n password hashes for each user, one that ...
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Is it safe to store a single symmetric key encrypted with several different RSA public keys?

For the field-based encryption of a database containing sensitive information, I was thinking of the following design: Every user has a smartcard used for client certificate login. After login the ...
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646 views

Does the SSL encryption strength of a website really matter?

When looking to get an SSL certificate one is presented with a lot of options. For example lets take Network Solutions since they have a nice comparison chart. Immediately there seems to be 4 major ...
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322 views

Protecting emails in your database

It's common to encrypt passwords in the database, but I'm wondering what solutions are out there to protect emails in your database. Not just from hacking, but from disgruntled employees or engineers ...
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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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3DES vs DES for VPN connections

I'm trying to get Android 2.1 phones to connect to our corporate VPN, but it would appear they only support DES rather than 3DES for encryption. Is it safe to use DES, am I going to get hacked if I ...
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Encrypting user data using password and forgot my password

I am planning to do a web application which stores a lot of personal stuff (info, photos...). And to give users a sense of protection, I want to encrypt the data before storing it to the database. ...
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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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319 views

Build a secure channel without SSL/TLS

I'm looking at possible options to build a secure channel between multiple embedded devices with limited cryptography capabilities and an HTTP server (It could be some sort of web service). 1. ...
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702 views

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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Authenticated Encryption vs. contained and encrypted checksum/hash?

So I read through http://en.wikipedia.org/wiki/Authenticated_encryption and http://www.cryptopp.com/wiki/Authenticated_Encryption and I don't seem to be following the concept. From the simple ...
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What role does cryptography play in anti-piracy?

As a follow-up to Cipher for Product Registration, are there secure yet usable cryptographic standards/protocols for protecting software and data used by software? I'm interested in hardware and ...
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How do you Secure VOIP in a large organization

As part of a large organization looking to implement VoIP, to get on the bandwagon of savings and converged network focus, I'm being asked to look at the security concerns to develop a policy to help ...
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314 views

Ideal way to store unhashed passwords

I'm dealing with a 3rd party vendor that clearly does not understand security - to access their API from my back-end I have to supply the end user's ID/user/password for the 3rd party service with ...
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1answer
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Android Device Encryption

I am trying to understand when using the default android device encryption in 4.0.4 ICS (AES-CBC 128Bit) how the Key Derivation Function works? That is how is the users decryption passcode transformed ...
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Is there any asymmetrically encrypted file system?

Is there a file system providing a directory where everybody can write, but only the directory owner can read the files? In theory it could be done by encrypting using the public key while writing, ...
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Copyright issues with encryption algorithms

I'm developing application for Android/Java. Application is a kind of password manager, so I'm storing encrypted passwords under the hood of master password. There are number of encryption algorithms ...
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558 views

It is possible that brute force attempts are successful before the worst case, correct?

When I read about a password being secure and stating that it would take X amount of week, years, etc. isn't that referring to the worst case? What happens if the brute force method is successul in ...
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1answer
764 views

Working out how to decrypt encrypted string when knowing the plain text

I have access to a system which I have been asked to create a data export routine for. However, the address details are encrypted and the original sourcecode/password are lost. However, I am able to ...
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Is RedPhone a secure and secret way to communicate?

RedPhone provides end-to-end encryption for your calls, securing your conversations so that nobody can listen in. But really, how is the probability that a voice conversation is wiretapped still? ...
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Unlock hard drive vs full-disk encryption

When I turn my notebook on, it asks me for the password to unlock the BIOS and than it asks me for the password to unlock the hard drive. How different is this 'password to unlock the hard drive' ...
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Using RSA with 3DES instead of plain 3DES. Does it make sense?

I have a large legacy code. Currently it is using 3DES encryption for a network based application. It encrypts data packets with a main key. This key is used to encrypt and decrypt (symmetrical). And ...
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How Reliably do mail systems transmit Encrypted PDFs

We have an solution design that will be sending Encrypted PDF's to our many clients, who will all be using varied email providers. We have tested the pdf's through the usual cast of internet mail ...