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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Is it possible to infer that a hidden truecrypt partition is likely to be present

Truecrypt contains a feature that let's you create a hidden volume. It's said that it can't be proven if a hidden volume exists. However, is it possible to infer from the state of the data on the ...
6
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1answer
441 views

OpenPGP Encryption / Decryption Process Using GnuPG

I want to know if my method of encryption can ensure the security of my data if my database was hacked as well as the authenticity of the data I am decrypting. I am using GnuPG's implementation of the ...
5
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6answers
600 views

What is the use of password encryption?

Why do we encrypt passwords? Is it to protect the password from eavesdropping? to protect the password after saving it in database? both? or for some other reason?
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9answers
4k views

What is the best way of securing a website logon without SSL or preshared keys?

Today I sniffed some unencrypted wlan traffic during class and I found quite a few passwords by a simple search for "pass" and "user" in wireshark. Turns out about half the sites we use for school ...
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5answers
8k views

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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3answers
2k views

How are mobile telephony networks like LTE and HSPA encrypted?

How are mobile telephony networks like LTE (4G) and HSPA (3G) encrypted? between what parts is the communication encrypted? who has access to the keys? is symmetric or asymmetric encryption used? is ...
6
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1answer
990 views

Select a TripleDES key so that it effectively behaves as regular DES

I'm working with a smartcard (DESFire) that supports both TripleDES and DES. In the specs it is stated that both modes of operation use 16 bytes keys. When the first 8 bytes in the key are identical ...
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2answers
581 views

What additional difficulties are present in performing ARP poisoning on a secure wireless network (WEP, WPA) vs. an insecure one?

I just finished a project in which I coded a man in the middle attack on an unsecure network. I've tried to see how feasible it would be to extend this a secured network. Some internet searching has ...
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1answer
541 views

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 ...
6
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4answers
3k views

If I send a fax from an unsecure endpoint to a secure endpoint, is the data secure?

I am very technical, but I do not know much about fax. I was told to send a fax to somebody with some very private information, and not to worry because they had a secure fax line. That's all well ...
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2answers
271 views

Do any crypto libraries take advantage of Windows GPU API “Direct Compute”?

Are there any encryption (decryption?) libraries that take advantage of the Windows GPU API?
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3answers
2k views

RSA 4096 with AES 256 Encryption Process Using PyCrypto

I have the following process for encrypting and decrypting data in a python script using the PyCrypto module: Encryption - Server A AES 256 shared key is generated Associated IV is generated Data ...
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2answers
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Digital Certificate deployment: using two certs for each user?

At a large enterprise environment I have come across a deployment approach for Digital Certificates where each user is issued two (2) key pairs: One for signing documents, emails, etc. that is ...
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3answers
8k views

Which SSL/TLS ciphers can be considered secure?

The OpenSSL website provides a long list of different ciphers available for SSL and TLS. My question is, which of those ciphers can be considered secure nowadays. I am especially interested in HTTPS, ...
5
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2answers
986 views

Have anyone tried to extract the encryption key from a SSD?

After reading this forum thread it does not sound like encrypted SSDs provide much protection at all - specifically encryption only occurs between the controller chipset and the NAND storage. Why is ...
5
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1answer
3k views

Protect access to an SD card

How can I protect access to an SD card, so that only authorized users can read or modify the content of the SD card. Currently everybody who has physical access to the SD card can read or modify ...
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1answer
12k views

What key exchange mechanism should be used in TLS?

There are many key exchange mechanisms that can be used in TLS. Among them are RSA, ECDH_ECDSA, ECDHE_ECDSA, ECDH_RSA, ECDHE_RSA and others. Which of these are more cryptographically secure and can be ...
7
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3answers
388 views

Secure cleaning of deleted files

So I know how to secure delete files. But at our company, we have a laptop which had many important documents, which now have been deleted, but not in a secure way. We can't perform a full format of ...
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5answers
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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 ...
10
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4answers
5k views

OS with encrypted RAM?

Are there any applications, JIT frameworks or operating systems that focus on encrypted virtual memory, or perhaps virtual machines that do something similar? I know there are processors (albeit old, ...
11
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2answers
2k views

GPG File size with multiple recipients?

If I encrypt a file for multiple users how does the file size change? Does the size of the output double for two users. How about 10 or 100 users?
13
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2answers
3k views

What's wrong with storing private keys in the cloud?

I know this sounds like a dumb question, but whats wrong with it? Assuming that all private data is encrypted (by the client) using PBE AES256, then is this scheme more vulerable than storing keys on ...
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9answers
5k views

Encrypting email for gmail

My friend who is an accountant was asking me what the best way to exchange documents with clients. He was trying to tell me that just sending via email was sufficient and I told him he was insane. I ...
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2answers
574 views

Using AES with a hex key/iv, what mode of operation is the “most secure”

I realize that is a loaded question, but it is not an unreasonable one. given a hex key/iv, what mode of operation is most secure from offline attacks. I defaulted to aes-128-cbc. Partly because of ...
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4answers
3k 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 ...
4
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2answers
213 views

When unlocking an encrypted drive, how does the unlocking program know it was successful?

This is very similar question to: If someone breaks encryption, how do they know they're successful? Basically, the answers to that question is that an attacker doesn't know when decryption was ...
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3answers
8k views

Why AES is not used for secure hashing, instead of SHA-x?

As far as I understand, AES is believed to be extremely secure. (I have read somewhere that it would certainly not be broken in the next 20 years, but I am still not sure if the author was serious.) ...
2
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1answer
660 views

What browsers support encryption or decryption using local certificates, or smartcard readers?

I am working on a cloud-based solution and I would like to encrypt / decrypt the data locally using either a SmartCard or local Machine certificate. I'm hoping to do this in Javascript, but may ...
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2answers
1k views

Is a JavaScript implementation of AES any less secure than other language implementations?

There are a few JavaScript AES implementations available such as Gibberish-aes So assuming the AES algorithm has been implemented correctly in this library then it should be as secure as any other ...
26
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4answers
14k views

How does PGP differ from S/MIME?

Is S/MIME an abstracted system for general MIME type encryption, whereas PGP is more for email? Why would I want to choose one over the other, or can I use both at the same time?
2
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2answers
434 views

How secure is Goodlink for mobile phones when compared to Activesync?

Some of our more technical users are arguing to use Activesync for their phones, while the corporate standard is limited to Blackberry and any device that supports Goodlink. One argument is the ...
3
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1answer
216 views

Can wildcard certificates hide/obscure the hostname in a TLS connection?

I'm trying to increase security for my cloud-based / multi-tenant environment. I'm considering having clients access an obscure URL such as GUID.myCloud.com. I will then respond to that guid-based ...
5
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1answer
547 views

Should I include a random padding in every HTTPS request and response?

According to the following paper, it is possible to decrypt HTTPS traffic by inspecting AJAX calls and using the size parameter as a cryptographic oracle. Should I be sending a variable length ...
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2answers
566 views

Why have export controls for cryptography?

I've always heard someone justify the means for export restrictions with "it's for governmental control/spying". In most reasonable countries, the justice system asks people to adhere to the "spirit ...
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2answers
3k views

What should I know before configuring Perfect Forward Secrecy?

PFS has gained attention in our audit department because of its innate ability to limit our exposure if someone steals our private key. What pitfalls or common mistakes should I be aware of before ...
5
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1answer
628 views

Clarification needed for NIST's whitepaper “Recommendation for Password-Based Key Derivation”

What are some sample use-cases the NIST is supporting in this policy / whitepaper regarding PBKDF2? This Recommendation specifies a family of password-based key derivation functions (PBKDFs) ...
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2answers
491 views

Inspecting a TLS Certificate to determine RSA Key Usage restrictions

With regard to this answer, I have a question about Key Usage in an SSL certificate. Most SSL server certificates have a RSA key which is not restricted through a Key Usage extension, so you can ...
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5answers
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Is there a simple example of an Asymmetric encryption/decryption routine?

I can understand Java, Perl and JavaScript code very well. The rest, I have not studied, but I guess I could figure out how to read/translate. I would like to know what the simplest of Asymmetric ...
22
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5answers
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What ciphers should I use in my web server after I configure my SSL certificate?

There are many great questions that ask what is the best certificate to use for a website; but once the certificate is purchased, there is also the possibility to choose or edit the Cipher list. ...
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2answers
1k views

SSL Breach - Does the latest BEAST vulnerability mean SSL Issuers now have to worry about integrity? [closed]

Although many SSL certificates have been boasting extravagant guarantees -- typically around $10k minimum to $250k per breach -- to ensure their certificates are valid, to this date, I've heard that ...
4
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2answers
664 views

Which is the easiest secure file transport protocol to implement (SFTP, FTPS, HTTPS, FTP over SSH, FTP over IPsec)

I have to select a secure file transfer protocol, to be implemented in a pre-boot system. I have access to libraries with the basic network functionalities (IP, TCP, UDP, etc...). I might also have ...
2
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2answers
5k views

How can I recover encrypted files after system reinstallation

I had a file which contains images and videos, I was using the windows 7 ultimate and I had encrypted the file. Now I have copied that file to my hard disk and format that operating system and again. ...
12
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2answers
507 views

Is it possible to have a key for encryption, that cannot be used for decryption?

For example, a server might have some encrypted logs or storage or whatnot, that would only be used for reference later. This way even if the server is hacked, everything is still OK until the hacker ...
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5answers
6k 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 ...
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2answers
833 views

How effective have statistical methods been at breaking encryption?

If we look at how statistical engines run on-line translators, and how they are built, we see that they look at a new language and run a statistical model over it searching for what's probably the ...
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0answers
271 views

Server side data de-duplication + client-side encryption with private key. Possible with “convergent encryption”? [duplicate]

Possible Duplicate: Online backup : how could encryption and de-duplication be compatible? I just saw an article on Techcrunch wherein a startup company was describing their new cloud ...
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3answers
617 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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5answers
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Asymmetric vs Symmetric Encryption

I am currently taking a principles of information security class. While talking about different encryption methods a large number of my classmates seem to believe that Asymmetric Encryption is better ...
4
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2answers
534 views

Protecting data on a laptop with linux

I'd like to keep some private data (photos, notes, ...) and my browsing data hidden. The rest is not so important. Most of the time I just put the laptop to sleep and don't shut it down often, making ...
2
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2answers
766 views

C# Encrypting string in DES 3 CBC mode

Is it normal that when I use Double DES secret key to encrypt a string in DES3 CBC mode then I always get the same cipher text? For testing I'm using IVC=0.