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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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, ...
8
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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 ...
6
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1answer
691 views

How do I learn Cryptographic/Mathematical notation

I asked a question earlier where it was recommended that I describe my issue using standard cryptography notation. How do I learn this notation and how to convey my approach? How can I annotate this ...
4
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2answers
145 views

Does adding a non-entropic part to a password makes it less secure?

Suppose I'm encrypting a file via AES using a password of my choice, or creating a TrueCrypt volume using a password and no keyfiles. Which of the following two passwords would be more secure: ...
3
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1answer
661 views

What are the Netscape Cert Type attributes? Why/when are they needed?

What are the Netscape Cert Type attributes in a X.509 Certificate and how are they different with the X509v3 extensions? Example: There is the Client/Server Extended Key Usage (X.509) but there is ...
3
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5answers
974 views

What's the State of the Art of Homomorphic Encryption?

I get the impression from some internet resources I have skimmed that homomorphic encryption is yet computationally very inefficient. However, an Infineon press release from 2010 says that the CPUs of ...
3
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2answers
178 views

Encrypting a fixed format message?

I'm planning to send across TWO pieces of information over the internet from machine A A site identifier which will be like: $SiteName = "EXAMPLE" (in plaintext) Encoded text which will be like: ...
2
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2answers
490 views

Determine encoding/hashing methods used based on knowing the input and output only?

If I know the initial value of a string and the resulting hash but have no access to the system that produces the output, how can I determine what has actually occurred so I can reproduce the hashing ...
2
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1answer
615 views

Vulnerabilities in Host Proof Hosting

I've recently been doing some research on Host-Proof Hosting, specifically in a web app environment. It seems like a pretty rock solid method of security, but I'm certainly not a security expert and ...
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1answer
192 views

Implementation review - Independent key, admin side and user side

The admin of the website needs to read user data. So, if the key is derived from the user pass, then the admin has to know the user pass, not exactly a good idea. The following encryption scheme was ...
1
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5answers
404 views

Does shuffling a hashed password increase its security?

I am making a web app and I'm now stuck on making the login secure. I'm thinking of adding a salt to a user-inputted password and then hash it. (md5 or sha for example) and then I will reshuffle the ...
1
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2answers
187 views

Seeking lightweight encryption - shareable between Delphi & C

I want to encrypt a text file in Delphi & decrypt it, line by line, in C on an embedded system which does not have much RAM (so, only one line in RAM at a time). FOSS must be available for both ...
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4answers
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What Are The Best Practices (Application Security Policy) For Modifying Rijndael Salt, IV, Pass Phrase

(Note: originally posted in SO - advised to post on SSE) With regards to Rijndael encryption, what (if any) are the best practices (and consequences) regarding the periodic modification of one or ...
1
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3answers
7k views

What does these warnings mean on an SSL connection by firefox (only)

I am connecting to a secure site and firefox mentions about identity: Owner: This website does not supply ownership information Verified by: Not specified Technical Details: Connection ...
0
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4answers
102 views

How does an encryption key work? [closed]

I'm having trouble understanding how an encryption key works. for example: if the word was 'hello' its encrypted value could be 'GHSSDgsd2', what would happen to the encrypted value if the key was ...
0
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1answer
92 views

Any issues with this security design for cloud storage? Server doesn't even need to know password to log someone in

I've created an algorithm I think I'm going to use for a cloud storage service I'm developing- if there are no issues or vulnerabilities with it. It's this along with TLS and forward secrecy ...
0
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1answer
1k views

Are there any known vulnerabilities in PPTP VPNs when configured properly?

PPTP is the only VPN protocol supported by some devices (for example, the Asus RT-AC66U WiFi router). If PPTP is configured to only use the most secure options, does its use present any security ...
0
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2answers
208 views

Security concern to implement a web based remote desktop

I am implementing a web based remote desktop application.Through this application client can connect to the server and can access the server using JSP/Servlet Java robot class. I can configure the ...
0
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1answer
310 views

Enterprise Encryption Considerations

What are the different aspects to consider for Enterprise Encryption policy? So far the resources I have are: https://www.owasp.org/index.php/Cryptographic_Storage_Cheat_Sheet ...
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1answer
480 views

Cascading Encryption Algorithm using mcrypt or GnuGP

I'm trying to a cascading cipher encryption algorithm to encrypt a textfile via mcrypt. I'm essentially trying to emulate the behavior of TrueCrypt, where it can cascade two or three different cipher ...
27
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1answer
6k views

iOS Encryption Details

Following on from this question Does anyone have any details/resources on the technical specifics of how apple implement encryption on their iOS 4.x series devices? The Apple marketing material here, ...
19
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4answers
12k views

Multi-boot with full hard drive encryption and pre-boot authentication

How would I set up a multiboot system which supports full hard drive encryption and pre-boot authentication. I have a system with Ubuntu, Windows 7, Windows XP, and I would like to install Red Hat. ...
13
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2answers
2k views

stronger encryption for SSH keys

I configured my server to encrypt user passwords using 500,000 rounds of SHA-512. The question is, how does the standard AES-128-CBC encrypted SSH private key stack up to that, provided the same (or ...
32
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2answers
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How secure is Ubuntu's default full-disk encryption?

How secure is the encryption offered by ubuntu (using the disk utility)? What algorithm is used underneath it? If someone could at least provide a link to some documentation or article regarding that ...
28
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2answers
5k 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: ...
23
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4answers
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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.) ...
12
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3answers
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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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13answers
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Why should I care if a site uses encryption or not if I'm not exchanging any sensitive data? [duplicate]

Lots of sites these days, that don't deal with sensitive data, enable encryption. I think it's mostly to make (paranoid?) users feel safer. In cases where there is a user's account being logged in, ...
19
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6answers
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Backing up sensitive data - pitfalls and best practices

Obviously, securely backing up sensitive data is a challenge. A remote backup is important for surviving a variety of disasters. What are some of the "gotcha's" lurking out there, and what best ...
13
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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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3answers
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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, ...
14
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3answers
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In PGP, why not just encrypt message with recipient's public key? Why the meta-encryption?

It's described very well by this diagram. It seems like the process used is convoluted and more round-about than it needs to be. Why is an intermediate random key generated for the payload's ...
4
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3answers
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How to roll my own security mechanism - avoid SSL

i'm looking at implementing my own security mechanism rather than using ssl due to ssl being 'hopelessly broken' http://www.theregister.co.uk/2011/04/11/state_of_ssl_analysis/ and also because it is ...
18
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2answers
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How does a crypter for bypassing antivirus detection work?

I am talking about crypters used to encrypt files like viruses and keyloggers for the sole purpose of bypassing antivirus detection. How do they work?
11
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1answer
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Secure Configuration of Ciphers/MACs/Kex available in SSH

Following on the heels of the previously posted question here, Taxonomy of Ciphers/MACs/Kex available in SSH?, I need some help to obtain the following design goals: Disable any 96-bit HMAC ...
4
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1answer
751 views

Whats the best custom compression method to use when I have SSL?

Suppose I have an application which does encryption using SSL and provided you cannot control what cipher suite is being negotiated, and assuming that I have some custom compression over the data ...
23
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2answers
1k views

What is the attack tree to intercept traffic on Wimax?

My current understanding is that sniffing traffic on 4G (lets use Wimax and LTE for the purposes of this question) and 3G is not a simple matter and either requires you setting up a fake base station ...
22
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2answers
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How can I check that my cookies are only sent over encrypted https and not http?

I read a blog post GitHub moves to SSL, but remains Firesheepable that claimed that cookies can be sent unencrypted over http even if the site is only using https. They write that a cookie should be ...
17
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3answers
2k views

How would you store a 4 digit pin code securely in the database?

I'm familiar with password hashing, using salts, bcrypt etc. But it doesn't seem like this would work to store a 4 digit pin code since the attacker could try all 10,000 combinations quite quickly. ...
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Confusion: Why isn't a passhrase encrypted SSH key two factor auth?

I'm trying to figure out the best practices for accessing my devbox from a public terminal. Most sources I've found recommend protecting the box with some kind of two factor authentication, such as ...
8
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4answers
429 views

What steps should one take to provide “reasonable” levels of privacy from a government?

I'm highly uncomfortable with the recent news surrounding government snooping in the UK. If we define a typical user to mean somebody who: Browses web sites such as BBC News and Stack Overflow Uses ...
7
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3answers
926 views

Truly deniable encryption

What tools can be used to make truly deniable encryption? Suppose, authorities can use any force to make you open your passwords. Truecrypt can have only one hidden container, which means that ...
5
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2answers
4k views

openssl: recover key and IV by passphrase

A large amount of files were encrypted by openssl enc -aes-256-cbc -pass pass:MYPASSWORD Openssl should derive key+IV from passphrase. I'd like to know key+IV equivalent of that MYPASSWORD. Is ...
5
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4answers
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Is client side encryption really better than server side?

Web application may encrypt all user data at client side to convince users that it can't decrypt them. When user enters password, it's used to encrypt data in browser and then it's sent to server in ...
3
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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 ...
17
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4answers
1k views

IPsec (Internet Protocol Security) facts

Internet Protocol Security (IPsec) is a successor of the ISO standard Network Layer Security Protocol (NLSP). What are the advantages, disadvantages, other interesting facts regarding the protocol?
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Is 7-Zip's AES encryption just as secure as TrueCrypt's version?

The main difference being TrueCrypt creates containers and 7-Zip encrypts the file itself, so file sizes can be guessed. Now let's just talk about the strength and breakability of the encryption. ...
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2answers
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Flaw in encryption through pseudorandom number stream (from gpg 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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6answers
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How can the impact of cold boot attacks be minimized?

Short of powering down and maintaining physical security for sufficient time, what are effective strategies for keeping keys from being disclosed by cold-boot attacks, and can anything be done without ...
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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? ...