Questions tagged [encryption]

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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47
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2answers
20k views

Web Application encryption key management

In a nutshell, let's consider a web application which stores some information in a database as encrypted data. While I'm purposely trying to keep this some what generic, here are some assumptions: ...
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Security comparsion of 3DES and AES

Which one is more secure and least possible to be broken through cryptanalysis AES or 3DES (no matter performance)? I need to use encryption for my projects to store and secure sensitive information ...
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2answers
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Is Signal still more secure than WhatsApp?

WhatsApp has "recently" deployed end-to-end encryption using the Signal protocol, which is of course also being used by Signal itself. The related white paper (PDF). Now this raises the question: Is ...
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2answers
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Store encrypted user data in database

I have a web application that has the following use case: User creates account with username and password -- hashed password is stored in database. User logs in (persists across sessions) -- login ...
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7answers
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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.) ...
48
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5answers
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HTTPS still NSA-safe? [closed]

There are exerpts, that say that using https can be broken by the NSA by now. So is https still a solution for secure web-browsing? source: http://www.digitaltrends.com/web/nsa-has-cracked-the-...
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3answers
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Why can a Tor exit node decrypt data, but not the entry node?

Me -> Node A -> Node B -> Node C -> destination The documentation on Tor always states that only the exit node C can see plain text data. How is this possible without me talking to Node C ...
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7answers
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What are the realistic, and most secure crypto for Symmetric, Asymmetric, Hash, Message Authentication Code ciphers?

I'm interested in updating this two pronged question for 2011: What cryptology is most appropriate for low-powered devices (such as a cellphone), and yet still effective? What cryptology is most ...
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17answers
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Can we still provide confidentiality when cryptography is outlawed?

In certain jurisdictions, use of cryptography by the private sector is limited: e.g. there are reports that in the UAE and other countries not all of the encryption capabilities of the BlackBerry are ...
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3answers
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Why do PGP master keys only have a single subkey, and tie certification with signing by default?

After learning more about PGP subkeys and how to split apart the roles of (S)igning, (E)ncryption, (A)uthentication and (C)ertification, I discovered that in most cases(?) a default master key has a ...
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8answers
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How does malicious software encrypt victims' files so quickly?

Encrypting a file to me is akin to dealing with a very long string, feeding it into the hashing or encryption function to get another long encrypted string (or a hash in the case of hashing). This ...
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4answers
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GnuPG decryption not asking for passphrase

I've some stuff encrypted with GnuPG using gpg -e. When I decrypt them, the system does not ask for the passphrase, it decrypts it straight away. Does it store the secret key somewhere and uses it (I ...
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9answers
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Is encryption in HTTPS done by the browser or by the system?

This may be a common sense question, but I am not able to find any documentation on this after searching on google for a long time When browser makes a HTTPs request, does it encrypt the data then ...
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1answer
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Does an HTTPS proxy encrypt traffic between proxy client and server for HTTP requests?

To bypass censorship in a DIY fashion, I plan to set up private proxies for my personal use. One of the possible methods I would try is to use an HTTPS proxy (not a web proxy, to be explicit) hosted ...
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2answers
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Strength of WEP, WPA and WPA 2 PSK

I know there are three method for wifi security. What are the relative strengths of the password encryption in WEP, WPA and WPA2 PSK?
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Encrypting With Passwords - Encryption of Key vs. Data

Many password-based encryption utilities (e.g.: KeePass, TrueCrypt) do something along the lines of... Encrypt data with super-strong random-generated key, "data key". Encrypt data key with another ...
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4answers
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Computationally simple, lightweight replacement for SSL/TLS

Target hardware is a rather low-powered MCU (ARM Cortex-M3 @72MHz, with just about 64KB SRAM and 256KB flash), so walking the thin line here. My board does have ethernet, and I will eventually get ...
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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 ...
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9answers
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Software that encrypts the data before deleting it

I am searching for a software that would encrypt data and then delete it (as opposed to just deleting or wiping). With that, even if the file is recovered, you still have to break the encryption to ...
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6answers
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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 encrypt ...
28
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3answers
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Use multiple computers for faster brute force [duplicate]

I've watched Mr. Robot lately and can't stop thinking why it was so hard to decrypt files encrypted using AES encryption with a 256-bit key. Let us say the only method to find the key is through brute ...
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4answers
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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 ...
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5answers
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What does LUKS header contain?

What is contained inside the LUKS header? I know, the header has size of 2MB. Also, cryptsetup supports "detached header", where the header can be stored in a separate file. Thus, for example, I can ...
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2answers
60k views

Decrypt from cipher text encrypted using RSA

I am sniffing a client side application traffic and I found some encrypted data. I am not able to decrypt it. Information which I have is Public Key: ...
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2answers
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Is it possible to use the aircrack-ng tool to crack a WPA2 Enterprise network?

is this tool (aircrack-ng) capable of cracking into a WPA/WPA2 Enterprise network? This tool has major success cracking the passwords of WEP/WPA networks. If it can, how, but if not, is there another ...
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Converting ECC Private key to PKCS#1 format

Is there any way to convert an ECC private key to RSA PKCS#1 format? I have tried converting it to PKCS#8 first using OpenSSL: openssl pkcs8 -topk8 -nocrypt -in EC_key.pem -out pkcs8_key.pem This ...
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5answers
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Why should one not use SSL? [duplicate]

I see a lot of posts all over the web asking whether or not they should be using SSL to secure their website, or if it's really necessary to do so when the content of their site does not contain or ...
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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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2answers
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Where should I store OAuth2 access tokens?

I am building a REST API back-end, for a mobile application. In our design choice, we decided to let OAuth2 providers handle the login security. However, I am not sure what the best practice is for ...
16
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2answers
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Securing remotely accessible IP cameras that do not support HTTPS

I have some IP cameras set up on my home network, which is WPA2 protected. These cameras are setup to be accessible from the Internet thru my router's DDNS address, and port number. So for example, ...
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5answers
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The AES Crypt implementation hashes a password 8192 times to generate the key. Is this necessary?

I'm considering encrypting some small files (hundreds of kb apiece) using the AES Crypt reference implementation. Looking at the source, it seems that the encryption key is derived from the IV and the ...
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4answers
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How would you analyze an image to find out if there are scripts embedded in it?

How would you analyze an image to find out if there are scripts or possible malware embedded in it? What tools / methods to use?
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Verify Login and Encrypt with PBKDF2

I'm writing a desktop application where I'm using PBKDF2 to generate an encryption key to AES-128 encrypt the config file. The config file contains a crypo-random key that's been used to encrypt the ...
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2answers
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TLS- Concept of channel binding

TLS-Handshake is based on public-key cryptography for symmetric key exchange, pki for server-authentication and assume the user authentication is realized trough username and password in the ...
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7answers
11k views

Is layered encryption more secure than long passwords?

The comments in this question debate about the added security of multi-layered encryption. There seems to be some disagreement, and I thought a proper question would be helpful here. So, to provide ...
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3answers
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What does it mean for a digital certificate to be “signed”?

When someone says that a particular digital certificate (like an SSL cert) has been "signed with a key", what does that imply? Does that mean the certificate simply includes a key that should be used ...
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3answers
13k views

Is SHA1 weak for SSL?

I noticed that today after I scanned a site on the Qualys SSL Labs site that SSL ciphersuites which use SHA1 are now highlighted as being "Weak". It seems this has just happened; I scan sites pretty ...
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5answers
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SQL field level encryption, how safe is it?

I am considering encrypting my database and/or encrypting only certain columns in a few tables. Is it worth the time? I mean, how much of a burden would it be on someone if they were to get a hold of ...
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2answers
37k views

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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4answers
14k views

Secure way to transfer public/secret key to second computer

I created a public/secret key using Seahorse (GNOME managing tool for encryption keys). I haven't had issues encrypting and decrypting files from the computer the keys are located in but I'd like to ...
9
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2answers
2k views

How the NSA can break trillions of encrypted Web and VPN connections

Based on Diffie-Hellman's negotiation of key exchange, why would it turn out that only a few primes are commonly used? What and who determines the prime? Would it not be safer to use a safe prime? (...
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5answers
4k views

Encryption for home ethernet?

I recently had my home wired for gigabit ethernet, which is awesome, but left me with a short ethernet run that is actually outside the walls of my house. How can I secure this link against someone ...
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3answers
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DEK, KEK and Master key - simple explanation

This article is intended to be a simplified explanation sans drill-down for people wanting to understand these concepts/terms. What are DEK, KEK and MEK/Master key?
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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
24k views

Is Bluetooth 4.0 traffic encrypted by default/design?

I wonder if the BLE (v4.0) traffic is encrypted by default or by design, or is it just optional? If the former, is the traffic encrypted using a key derived just from the pairing pin or is there some ...
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5answers
6k views

Is it feasible to encrypt customers personal data? (name, address etc…)

Seeing the Sony Personal data kerfuffle unfold has gotten me thinking about the encryption and securing of personal data - obviously credit cards can (and should) be encrypted, making data breaches of ...
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1answer
2k 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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5answers
3k views

Can voice chat be spied?

I wonder if voice chat (via public services like yahoo, google talk, skype, etc) is practically secure? Is it possible for the ISP or any middle point? I do not consider hacking the computers, but ...
11
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1answer
6k views

How to choose a stream cipher

Are there high-speed ciphers designed for things like internet streams without sacrificing security? There are so many options that operate in stream mode. How would one choose a cipher?
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1answer
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Cellular encryption algorithms currently in use globally

I have been doing research on the available encryption algorithms used by commercial mobile providers worldwide, and would like to know if the following list is complete: Algorithms for voice ...

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