Tagged Questions

0
votes
1answer
54 views

PCI 3.6.6 cryptographic key procedures include split knowledge

My question is, if you run your own company and there are no employees and you still qualify under assessment D what do you do in a case like this where it is requiring 2 or more people? On a related ...
1
vote
1answer
132 views

Exchange of DEK and KEK (encryption keys) between app server and key server

In my application, it is required to encrypt a user's data before inserting it into the mysql database. I am using AES algorithm to encrypt the data using a 256 bit hash (and is calling it Data ...
0
votes
2answers
185 views

Where do I securely store application-specific symmetric key?

I am writing an application App1. This application uses SQLite database and I plan to encrypt it using AES256. For symmetric encryption I need a key, which I need to store somewhere. From a similar ...
6
votes
1answer
285 views

Encrypting sensitive data in software and storing/decrypting it on a server

I have searched IT Security and Google for something similar to this, but wasn't able to find anything remotely related to what I'm doing. I'm developing software which has 2 parts - a C# program run ...
3
votes
4answers
165 views

Using dynamic keys

It is intuitively clear that, the less materials a cryptanalyst has available to work on, the lower would be his chance of success. This implies that the security of encryption of a message could be ...
4
votes
1answer
826 views

Encrypting data for Android mobile app

I am creating a mobile app for Android. This is my first mobile app by the way. I have decided to store data used in my app in a SQLite database in the target Android device. The data I am storing ...
0
votes
2answers
183 views

In depth security: splitting key in different places

I use AES encryption on a website. At the moment, the key is stored in the source of the PHP script that does the encryption/decryption process thanks to openssl. I know that it isn't secure, so I ...
7
votes
3answers
291 views

AES using derived keys / IVs. Does it introduce a weakness?

I'm looking for an efficient way to encrypt multiple fields in a database with AES using a single global key, used throughout a large web application. Obviously in order to re-use this key, a unique ...
6
votes
1answer
70 views

What is the best way to manage package signing keys?

I am researching a way to protect, and enable accountability of, our packages when being transferred from our dev team, through to Q+A and eventually to deployment. I have initially created a signing ...
2
votes
1answer
105 views

Security of re-encryption with a list of pre-computed password based keys

I have a problem where an encrypted file stored on a server needs to be decrypted through a precomputed list of passwords that are used one time only - OTP applied to encryption basically. The file is ...
1
vote
1answer
226 views

How to protect encryption key while application is using it

I made an J2SE application that uses AES (in CBC mode using BouncyCastle library) to encrypt application config file & some user provided files. I stored the raw AES key in a file that is ...
4
votes
3answers
183 views

Security in wireless ad hoc sensor network (without physical access)

I want to know without taking physical access, what are the methods that can steal the data in a node. When talking about eavesdropping, how can an attacker sniff the packets? Do they need to listen ...
1
vote
1answer
124 views

How dependable can data encryption be without re-entry of password on startup?

I posted a comment awhile back, and thought I would turn it into a question. Example: There is a feature in the Microsoft SQL Server for full database encryption, which seems to have an option that ...
0
votes
1answer
260 views

How do I securely store and retrieve a many-time use key?

I am performing some symmetric database encryption/decryption in .net. I am using a single 256 bit private key. (1) Where do I store this key when not in use? (2) How do I securely retrieve this ...
4
votes
3answers
310 views

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 ...
7
votes
2answers
1k views

Using RSA with 3DES instead of plain 3DES. Does it make sense?

I have a large legacy code. Currently it is using 3DES encryption for a network based application. It encrypts data packets with a main key. This key is used to encrypt and decrypt (symmetrical). And ...
5
votes
2answers
699 views

Using TPM with DMcrypt?

Is it possible to use TPM for storage of some private key? It's not a full-disk encryption , I want it to be compatible with existing LUKS, just add another key, and store it in the TPM.
1
vote
1answer
229 views

Hybrid key management doing it wrong?

I'm currently working on a project that needs be as secure as possible key-management. My experience with encryption, decryption and key-management are none whatsoever so i did some research on the ...
5
votes
3answers
3k views

What is the DUKPT Key Derivation Function?

I'm tasked with decrypting ciphertext acquired from an encrypted card reader. The card reader utilizes DUKPT(derived unique key per transaction) scheme and 3DES encryption. I don't have a problem with ...
2
votes
1answer
417 views

How to use DPAPI under load balance environment

DPAPI can be used to encrypt the secret data. We intend to use it in our web app to encrypt some data and store the encrypted data in database. When needed we decrypt the data and present them on ...
9
votes
2answers
3k views

where to store a key for encryption

I am looking for a way to store a key used for password encryption. I am using a mysql db which would store a user name and an encrypted password that would be encrypted using ...
3
votes
2answers
763 views

How to store IV and key temporarily but securely

I am using .NET 4.0 to develop a Windows service that will temporarily store encrypted data in a database. The data will be encrypted when it is inserted, then decrypted, processed, and deleted once ...
3
votes
1answer
486 views

Storage of 'secrets', keystores, HSMs and the rest

I've been digging for the past few days into storage of sentitive data. If I store this data in a database, I believe the general accepted practice is to store sensitive data encrypted, for various ...
5
votes
1answer
2k views

Creating a “key server” (HIPAA compliance with AWS)

I'm a part of a small company that is going to be implementing HIPAA compliance. We will be seeking legal counsel, etc so anything heard here will not be taken as legal advice, etc. I just want to ...
9
votes
4answers
2k views

Does symmetric encryption provide data integrity?

Let's say I have one server that encrypts a file with a symmetric key, e.g. AES-CBC, and sends it to clients that decrypt it. Does that provide data integrity when decrypted? Or is it possible for ...
6
votes
5answers
3k 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 ...
2
votes
3answers
1k 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 ...
11
votes
2answers
1k 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 ...
7
votes
3answers
407 views

Server to server encryption: Key rotation over the air. Can it improve security?

In my other question, I explored whether to write my own encryption or use an existing one. I was advised to use TLS or AES or something that is established. This question is about key rotation. It ...
3
votes
1answer
363 views

Is this security/encryption scheme secure?

I'm rolling my own, personal threetags.com-style 'encrypted data in the cloud' webapp (I didn't like the UI, and lack of non-browser client). However, I have absolutely no experience with security ...
12
votes
6answers
620 views

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 ...
72
votes
3answers
44k views

RSA vs. DSA for SSH authentication keys

When generating SSH authentication keys on a Unix/Linux system with ssh-keygen, you're given the choice of creating a RSA or DSA key pair (using -t type). What is the difference between RSA and DSA ...
9
votes
5answers
1k views

Use RSA keypair for PGP encryption and decryption

Is there a way that I can use a RSA keypair with PGP? What I mean is that I have 2048 length keypair and i want to use that to encrypt and decrypt data. But all I have found is that the PGP uses some ...
4
votes
2answers
2k views

mysql AES_ENCRYPT key length

AES_ENCRYPT uses a 128 bit long key to encrypt the data, but how does mysql handle longer or shorter keys? I found out that pycrypto for instances recomend to transform the key by using md5 sha1 sha2, ...
19
votes
2answers
3k 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: ...
3
votes
1answer
148 views

Help on interpretation of FIPS-140 paragraph

This is from the FIPS 140-2 standard: Cryptographic keys stored within a cryptographic module shall be stored either in plaintext form or encrypted form. Plaintext secret and private ...
8
votes
3answers
738 views

Security implications of storing the password hash along an encrypted AES key

I am using the PKCS#5 standard to generate a key using a random and unique salt and the user's password in input. Consider this key as the "encryption" key. The "encryption" key is used to encrypt a ...
3
votes
3answers
106 views

Encrypting a fixed format message with commands and transmitting over the internet

Linked to: Encrypting a fixed format message? I need to communicate from Site A, a set of information that will be presented to users of Site A, which when they choose to submit, should travel to my ...
3
votes
2answers
157 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: ...
5
votes
1answer
289 views

Is storing a private key in a device as it was done in AirPort Express the right solution?

Here's a story about how one guy reverse engineered AirPort Express and obtained the private key that was used to prevent cloning the device ability to stream audio to approved devices only. So ...
7
votes
2answers
1k views

Data Encryption and Key Management in C#

Which route to take, what are the pros and cons, which is more secure.. Generate AES key, encrypt the data with it and then encrypt the AES key with RSA, save the encrypted data and encrypted AES ...
12
votes
4answers
781 views

Is Steganography considered encryption and subject to USA export restrictions?

I have written an application for Apple's iOS which embeds messages in JPEG files using steganography (see http://en.wikipedia.org/wiki/Steganography). For the purposes of this question lets assume ...
9
votes
3answers
3k views

Encrypting with Mongo

How can I achieve the following goals? All compute and storage to be located in the cloud. Encryption in transit of all data between web nodes and db nodes running MongoDB. How to set up tunnels? ...
4
votes
3answers
297 views

Are there any serious problems with this technique for generating symmetric keys?

I'm using a technique borrowed out of a book by Bruce Schneier and Niels Ferguson called Practical Cryptography. Basically, it boils down to this: Bob does this: pubk_A = Alice's public key ...
8
votes
5answers
7k views

Compute the AES-encryption key given the plaintext and its ciphertext?

I'm tasked with creating database tables in Oracle which contain encrypted strings (i.e., the columns are RAW). The strings are encrypted by the application (using AES, 128-bit key) and stored in ...
8
votes
5answers
338 views

What can one do when encryption methods fail?

I'm in search of an expert to answer my curiosity. Suppose that methods like AES/DES, SSH, PGP, RSA, etc. can be cracked or fail somehow. In other words, suppose that it's possible to determine one ...
9
votes
5answers
1k views

Storing private asymmetric key in application binary?

I would like to give a daemon-style process (i.e. no user interaction) access to a shared secret key so that it can access a shared, encrypted data file. User applications accessing the same encrypted ...
8
votes
3answers
1k views

What common products use Public-key cryptography?

I want know what common use products are there that use public key/private key cryptography?
7
votes
3answers
402 views

Database Encryption Security

I am encrypting and decrypting my database data from my web applications API. If my web server is compromised, what is to keep someone from using that same method to retrieve the data? For example, ...