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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Doubling up or cycling encryption algorithms

I've occasionally read the suggestion to enhance security by either doubling up on encryption algorithms (encrypt a message once with one algorithm, then encrypt the ciphertext again with a different ...
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1answer
773 views

How long would it take to brute force the AES encryption?

I'm trying to write a secure code that can keep my site users passwords as safe as possible. Now I'm fairly new to encryption and would like some professional opinions and suggestions. As well as a ...
1
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1answer
381 views

NTRU java attack implementation

I'm researching NTRU cryptosystem and started research based on source code from sourceforge and bouncy castle(java language). Currently I'm reseacrhing attacks on NTRU, based on CVP and SVP. But I'd ...
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2answers
894 views

Using a Common Private Key for Digital Signatures

I have a mobile application and a server. The mobile application communicates with the server through a web services framework via SSL. The mobile application allows customers to pay for ...
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1answer
1k views

Is the connection between Gmail server and Apple server encrypted? [duplicate]

When I send an email from my gmail account to another mail server (apple, microsoft, yahoo...), is the connection encrypted in the path between the two servers?
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1answer
815 views

Is server-side cryptography with user-only access possible for email services?

I came across the Lavabit High Scalability Writeup and got curious. Do you use any particularly cool technologies or algorithms? The way we encrypt messages before storing them is relatively ...
6
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2answers
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What risks are there with a Bluetooth based door lock, and are there any mitigations?

There are a few interesting Bluetooth door locks on the market that use version Bluetooth 4.0 however there seems to be a few issues with this E0 Encryption flaws Risks during pairing Attacks ...
3
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2answers
796 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 ...
4
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3answers
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How are possible uses for X.509 (SSL) certificates denoted?

X.509 certificates can be used for servers, clients, email, code signing and more applications. http://twitpic.com/6gdxaq indicates that a certificate can have different of these 'capabilities' on it -...
4
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2answers
633 views

Preparing for a stolen physical server

What would be the best ways to protect sensitive data stored on a server/drive that gets stolen? The confidentiality of the data is what is important, not retrieving it. Obviously, physical means are ...
1
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2answers
196 views

Name of security system

This is a security system that I would like to know the name of, here is a description: I have heard that some people will use a separate computer for decrypting messages. When they revive a message ...
0
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2answers
263 views

A thought experiment about obfuscating the location of a smartphone when it is in use, is it possible? [closed]

I was thinking about how smartphones are very difficult to use in a way that does not transmit your location, with all the networks it has to connect to (and let's say a 'burner phone' is too ...
6
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2answers
3k views

How do I know if my encryption algorithm is strong enough?

I am using ruby and have the following encryption algorithm: @@secret_key = Digest::SHA256.hexdigest(key) encrypted = Encryptor.encrypt("encrypt this", key: @@secret_key) encoded = Base64.encode64(...
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3answers
1k views

wpa2-psk + wireless isolation = secure connection?

from what I've read: If I am on a wireless network without encryption, any other computer connected to that same network could easily (with right tools & knowledge) intercept any traffic I send/...
0
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1answer
109 views

Does adding an extra, non-entropic keyfile lower security? [duplicate]

Suppose I create two TrueCrypt volumes using keyfiles. The first volume uses a keyfile generated by TrueCrypt, whereas the second one uses the same keyfile in addition to a second, non-entropic ...
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3answers
2k views

Implementing 'Remember Me' for a mobile application

I am developing a mobile application wherein I need to implement the 'Remember Me' functionality. There are certain pages within the application which require you to login. What I need to do is, if ...
2
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2answers
446 views

Pre / post disk encryption wipe?

When dealing with full disk encryption a lot of utilities I've worked with will provide the option to fill the disk with random data to make distinguishing the encrypted contents harder to identify. ...
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1answer
1k views

How does paypal store credit card numbers?

How does Paypal store credit card numbers? Have they published any information this? As for now I would say that they encrypt the card numbers and store the key in an HSM, but this is just a ...
5
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1answer
3k views

When do I use NIST AES key wrapping?

Key Wrap constructions are a class of symmetric encryption algorithms designed to encapsulate (encrypt) cryptographic key material. The Key Wrap algorithms are intended for applications such as (a) ...
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1answer
889 views

How to encrypt by AES-Twofish-Serpent

I was wondering how to encrypt by doing a AES-Twofish-Serpent encryption. Does this mean I encrypt in AES first then after that in Twofish, and after that in Serpent (three separate encryptions). ...
11
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3answers
1k views

OpenSSL generates 1032bits when I request 1024bits

When I enter the command-line openssl dhparam -text 1024 the resulting safe-prime is 1032 bits instead of 1024 bits. It seems like the 1st byte is always 0. Why is this?
2
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1answer
385 views

Unknown encryption string [closed]

I'm trying to learn about encryption and decryption methods when I faced this string: {MD5}JfnnlDI7RTiF9RgfG2JNCw== MD5 is 16-byte string, so anyone know what type of encryption is this and why ...
1
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0answers
149 views

Formatting before encrypting [closed]

Is formatting a device before encrypting more secure as opposed to encrypting the device without a formatting?
6
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1answer
2k 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 ...
9
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1answer
24k views

Getting “SSL: alert [”write“]: fatal : bad record mac” during openssl Handshake

I am getting SSL: alert ["write"]: fatal : bad record mac from the OPENSSL logs during the handshake and Client is not sending the Application data and its creating the handshake again and again. ...
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2answers
573 views

Can AES-256 encrypted data be changed?

I have a file that supposedly contains AES-256 encrypted data. The file was created using a proprietary program that claims to use AES-256. I have tested decrypting the file with an open source ...
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1answer
463 views

Encryption algorithm encryptable by md5 of key and decryptable by key [closed]

Is it possible to make an encryption algorithm that can be encrypted by the md5(or any other one way encryption algorithm) of the key and decrypted by the key? The purpose of this would be for the ...
4
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1answer
117 views

Are there any public examples of an encrypted attribute in a Verisign-issued certificate?

This Credentica- UProve paper describes how Verisign issues (or did issue in the past) certs with encrypted attributes: "VeriSign issues certificates that contain encrypted attributes that can be ...
6
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2answers
2k views

If encrypted data in a database are accessed by application, does that mean that the application has the decryption key?

I'm using an application linked to a database which holds confidential data (numbers). According to the developer, this data is encrypted. However, i can easily generate a report that will show the ...
3
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2answers
2k views

Deduplication of Encrypted Files

Let's assume I have an 18GB database that is backed up nightly by dumping the database and then encrypted using a modern algorithm such as AES-256. This database has a daily update of rate of ...
0
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2answers
366 views

encrypted cloud storage with partial local copy

Is there a cloud storage solution with the following features: partially copied locally. Not fully like dropbox so it can be larger than the local disk. Not fully in the cloud but just a local disk ...
3
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2answers
751 views

Store private key on server, then use k1 to log in, k2 to verify HMAC and k3 to decrypt private key

I'm working on a proof-of-concept program to encrypt email with less difficulty for end-users with a process like: To create an account: Generate a random salt and IV, and get a password from the ...
38
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5answers
3k views

Client-side encryption, but cloud service can still decrypt data in the event of a death? Is this possible?

I've been worried about this password manager, PasswordBox that seems to be gathering quite a bit of steam lately. They seem to have raised VC funding and are offering a free password management and ...
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3answers
569 views

PHP web application security [closed]

I am building a PHP web application, that needs enhanced security, due to the fact that it contains very sensitive information (in a database). I think that I want to use self-signed SSL ...
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1answer
678 views

Is decryption using Java+JSF safer than using JavaScript?

First off, this is in addition to using SSL! I am building a web application that receives encrypted data from a server. The data is to be decrypted client-side. I've read enough posts here to see ...
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1answer
3k views

How do I unencrypt emails from a pst file without a digital certificate? [closed]

I saved a pst file on a CD. It contains a lot of email that was sent to me using a digital signature. I am now in a lawsuit and need to print out those emails but no longer have access to my digital ...
36
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3answers
2k views

Am I wrong to believe that passwords should never be recoverable (one way hash)?

I recently forgot my password for our cable provider online account, only to discover that they sent it to us via plain text in an email. I quickly sent an email to customer support asking them if ...
5
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5answers
759 views

Encrypted disk at risk if laptop stolen while turned on but locked

If I have a laptop with full disk encryption it's turned on, the screen is locked and it gets stolen. How would an attacker get my data? It's not encrypted at the moment because it's turned on but the ...
5
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2answers
5k views

I am always Hibernating my System, is there any risk for my Encrypted drive with BitLocker?

I am Always Hibernating my Laptop, for faster booting, I encrypted sensitive drive by BitLocker, what if my Laptop stolen and attacker knew that it was in hybernate mode, can he decrypt my hard?
10
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4answers
639 views

How can I audit which type of Block Mode encryption is being used when no source code is available?

Given that there are clear advantages to using some block modes of encryption over another, and I would like to ensure that all software used in the enterprise uses a certain "level" of security I'd ...
5
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2answers
416 views

Security of PGP for Long-Term Storage

How secure are PGP/GPG encrypted mails? I realize that it's probably fine for regular e-mail scenarios, but what about the security over longer time periods (>30 years)? Is the 4096 bit limit for ...
1
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1answer
215 views

The basics of cryptanalysis [closed]

There are a lot of books on encryption. Is there a must read intro, something like Smashing the Stack for Fun and for profit, that more or less everyone reads?
8
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2answers
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Ubuntu LVM Encryption

I recently installed Kubuntu and I noticed the option for having an encrypted LVM. The behavior suggests it's full disk encryption since I need to put in a password before I can boot. This article and ...
4
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1answer
964 views

BitLocker with Windows DPAPI Encryption Key Management

Disclaimer: I realize that I posted this question on ServerFault, but I have not received any response there. I am hoping that this forum might be a more appropriate place to post this for a response....
5
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2answers
154 views

Is there a reason to encrypt an encryption key with a certificate before storing it?

Suppose my .Net application which is installed in the client encrypts a data. I want to use a different key generated randomly for each client so each client doesn't know the key of the other. Someone ...
2
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2answers
934 views

Least insecure way to encrypt a field in the database so that it can still be included in queries

I have a table where all columns need to be encrypted (aside from the PK). This will be achieved using AES at the application level. However there is one particular field that needs to remain ...
3
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1answer
1k views

Can you make a digital signature using the receiver's public key?

My question is, can you make a digital signature using the receiver's public key and then have the receiver verify the signature using his private key? I always thought that in order to create a ...
1
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1answer
305 views

End to end cryptographic methods/solutions

I want to implement secure communication for my application. The A sends a message/data and B receives it. The message should be encrypted so the internet provider would not be able to read it even if ...
3
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1answer
865 views

Why does broad based malware use XOR obfuscation?

As per title... The malware can easily be de-obfuscated if it was obfuscated using common and known XOR techniques. Why don't malware authors use any other method that make it much harder to ...
3
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4answers
914 views

Would a predefined shared secret key be good here

I'm a software developer working with hardware devices that are deployed on the field. Every now and then, I would need to update the hardware's firmware (upgrades, patches, etc) I'm thinking of now, ...