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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AES CBC over TCP - when is new IV needed

I am working on a project where two devices will be communicating with AES with CBC over TCP. We already have a secure mechanism for sharing the encryption/decryption key. I am not sure if we need to ...
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1answer
2k views

When authenticating ciphertexts, what should be HMACed?

Some have argued for using AES-256-CTR with HMAC-SHA-256 for authenticated encryption over AEAD-specific modes like EAX and GCM. However, when doing, this, what should be HMAC'd? And how? ...
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1answer
1k views

Encrypting configuration on shared IIS7 hosting that uses load balancing

When hosting a site on a cluster (or cloud configuration) we need to specify a Machine Key in the web.config file. This is needed to keep the machines in sync (often the first encounter with this is ...
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3answers
3k views

Is encrypting data with a private key dangerous?

I have been reviewing code for various internal apps that handle secure transmission of data with external systems. These follow the following process: RSA encrypt data with 3rd party public key RSA ...
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1answer
340 views

How key_derivation and key_verification functions are implemented of a 7-zip archive's encryption mechanism?

I am curious about how password recovery works for password protected files. And I want to know the exact flow of the 7-zip encryption mechanism :) !! 7-zip uses the AES-256 encryption algorithm in ...
3
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1answer
421 views

DPAPI offline attack by cracking windows password?

I'm thinking of using DPAPI to protect configuration file information in my program. After doing some reading on it, it looks like it uses the user's Windows password as part of the encryption ...
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3answers
569 views

Linux mcrypt security

I just installed 'mcrypt'. When I try to encrypt some file with DES using the command 'mcrypt -a des myfile', I am prompted for a passphrase with a maximum character count of 512. > mcrypt -a des ...
5
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1answer
281 views

What issues might exist with TLS-OBC's emulation of Browser Certificates?

TLS-OBC is an RFC proposal that increases SSL/TLS security by using certificates on both ends of the TLS connection. What's special here is that the client is permitted to dynamically create a local, ...
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4answers
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Is encrypting a salt value with a password/plaintext a viable alternative to straight up hashing?

The basic problem, as far as I can tell, is that hashing's flaw is that the password is in the hash. Asymmetric encryption's flaw is that the password is encrypted and can be reversed. The posts ...
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2answers
1k views

Does using both GPG encrypted files and encrypted filesystem make sense?

For a few years i stored my personal text files encrypted using an asymmetric key through GnuPG. Now i thought that it is a good idea to also encrypt my hard drive partition. Does it make sense to use ...
8
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3answers
2k views

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 ...
11
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5answers
4k views

Is it worth the effort to store FTP passwords encrypted?

I have a project to build a system that needs to push files to multiple third-party FTP servers. I have asked these third parties to provide a more secure interface; all have declined. So now I have ...
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1answer
2k views

Should WPA2-AES be presumed insecure? (What is the “Hole196” vulnerability?)

I saw it mentioned in an answer here about firesheep, but I've never heard of it -- Should WPA2 be presumed insecure?
3
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3answers
408 views

Without SSL, what vantage point does one need to MITM non-SSL'd HTTP?

OK, so there are two things here: being able to read the content of the requests and responses, and then being able to modify them. The former may depend on the latter, I'm not sure. But basically, ...
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3answers
4k views

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 ...
5
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2answers
635 views

Shibboleth user attribute encryption

How does Shibboleth guarantee that 3rd parties do not get access to user attributes contained in SAML 2.0 assertion exchanged between IdP and SP? Is it correct that all user attributes are encrypted ...
7
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2answers
5k views

Storing password in Java application

What is best secure way to store passwords in Java web application? I am not talking about password to the DB, so it must be stored in de-cryptable way. It’s cloud environment and I need to protect ...
7
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2answers
2k views

MAC vs Encryption

I understand the difference between MAC (eg. hmac_sha256, etc.) and Symmetrical Encryption (eg. rc4, etc.), but my question is what advantage does MAC solve that using encryption doesn't? I know that ...
4
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2answers
591 views

Security concerns about my webapp

I read though OWASP very carefully, but I am not sure about some parts of my website. I am using jbcrypt on my website. It stores the salt in the hash itself something like this hash+salt. I read ...
3
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2answers
266 views

Unecrypted connection to server - safe?

I am using heroku and cloudflare. I am going to release my website but I don't want do it without SSL. Now I always need an heroku addon to add my SSL certificates which costs $20/month. Cloudflare ...
8
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4answers
1k views

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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6answers
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What are the good use cases for disk encryption?

I've been researching disk/file system encryption, and on the surface it seems like a good idea for a lot of things. But as I dig further, the security it offers seems more mirage like than real. ...
5
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1answer
375 views

SSL CipherSuite Choices

In SSL/TLS, is the CipherSuite chosen by the server or the client? Also, can the certificate in any way dictate or modify the CipherSuite?
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4answers
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What kinds of SSL certificates are usable for encryption?

I know that Verizon SSL certificates cost close to $600. There are couple of cheap alternatives, but I never really understood why Verizon does not offer such certificates. Look for RapidSSL at ...
12
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4answers
1k views

Encrypting IP addresses in a MySQL database

I'd like to encrypt IP addresses in my MySQL database, with the following constraints: Does not need to be resistant to attackers that can execute queries. Must be resistant to attackers that have ...
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3answers
916 views

Encryption-Laws in Iran

According to this article Iran has criminalized the usage of encryption and VPNs. According to this blog post it is still possible to use SSH tunnels in Iran. For me SSH is encryption and thus ...
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6answers
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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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2answers
3k views

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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5answers
21k views

SHA, RSA and the relation between them

SHA is the hashing mechanism. However, RSA is the encryption algorithm. So does RSA algorithm use SHA hashing mechanism to generate hashing keys which in turn is used to encrypt the message?? ...
8
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4answers
2k views

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 ...
2
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3answers
2k views

Is SSL Tamper Detectable?

I know how SSL provides security against people reading your messages - by encryting the message with a SYMMETRIC KEY, which was exchanged during SSL Handshake with the help of ASYMMETRIC KEYS. But I ...
4
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1answer
1k views

Encrypt Medicare card numer in C# in ASP.NET

I am giving a free consultation for a non profit organisation that wants a simple system to manage multiple groups with a schedule component, etc. and also manage the medical informations of the kids. ...
6
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3answers
536 views

Embedded System Communications Security

I am getting ready to start deploying an embedded sensor network that is internet connected (via the cell network) and reports private data on a regular basis back to a central server. Unfortunately, ...
16
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2answers
4k 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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2answers
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ssh public/private key pair

I am having problems understanding how ssh really works. I know it uses a public key cryptography to encrypt messages. However, I can ssh to a server without first generating a public/private key pair ...
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2answers
1k 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 ...
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2answers
225 views

What number of bits does a browser use to generate a key?

The question comes from the accepted answer in this thread: My understanding of how HTTPS works (gmail for example) The Gmail server sends your client a certificate. The certificate includes the ...
6
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1answer
271 views

Could a consumer-friendly PGP-like file encryption application theoretically be secure?

In a situation where there are desktop and mobile clients, and a central public key repository to and from which the desktop and mobile clients automatically upload and download public keys as needed, ...
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2answers
4k 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?
5
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1answer
501 views

Asynchonous Linear Feedback Shift Register : test vectors

Well I've been working on coding LFSR structures for my research projects. Being able to find sources on the subject, I've been able to test a single LFSR with different initialisation and TAP ...
7
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2answers
433 views

PKCS#5 Salt privacy? [duplicate]

Possible Duplicate: Password Hashing add salt + pepper or is salt enough? In the official documentation of the PKCS5 V2.0 standard, we can read "The salt can be viewed as an index into a ...
3
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1answer
577 views

Are SSL Certificates (Private and Public key) generated by OpenSSL and makecert compatible?

Are RSA SSL Certificates (Private and Public key) generated by makecert compatible with OpenSSL decryption ie. can I decrypt them with the openssl_* methods? I am working on two-way SSL authentication ...
18
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4answers
2k 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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3answers
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Is the OpenPGP private key inherently password-protected?

I know I am required to enter a password every time I use my OpenPGP key. Is this done via software implementation or is it a property inherent to the protocol, and therefore the key? Essentially, ...
4
votes
1answer
186 views

How does my antivirus determine which CTL is used?

I have imported a trusted root certificate into the Windows local machine list. This works fine with my signed certificates, unless my AV (Bitdefender Antivirus Plus 2012) is set to "scan SSL", in ...
2
votes
1answer
795 views

Encryption key token

How to securely store an encryption key in USB drive? Here is my idea. I would like to write a program (let's say PC) and it will store data to a database encrypted at the record level or field level, ...
11
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5answers
1k views

what would be a good way for a doctor to send xrays encrypted to another doctor?

As a dentist, I often want to send medical information including digital xrays to another doctor. What would be a good/easy way to do this encrypted? Our organization currently requires that all ...
4
votes
3answers
354 views

Secure File Encryption/Decryption Capabilities

As a preface to my question, let me state that I'm a relative newbie in the field of security. I work for a back-office financial software provider that is responsible for processing, generating, ...
4
votes
2answers
751 views

Can you encrypt a password using that password itself? [duplicate]

Possible Duplicate: How to securely hash passwords? https security - should password be hashed server-side or client-side? I need to make a request to a web server, the only information I ...
14
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2answers
9k views

For LUKS: The most preferable and safest cipher?

I'm about to encrypt two of my hard drives using LUKS, since I can't really do it myself I use the guide on the Arch Linux wiki (which can be found here). In an example in the guide the cipher ...