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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6answers
10k views

How do I prevent copying of my PDF files?

One time while I was printing my documents at a copy center, I saw they dragged-and-dropped my PDFs from my flash drive to their desktop. How do I protect my files without using password? Is there a ...
2
votes
1answer
2k views

Open source video conferencing software with encryption [closed]

A couple of friends and I are looking for an open source video conferencing software. We'd like to run the server on a Debian box, but the clients are Windows machines. Most importantly, it should ...
2
votes
4answers
214 views

How does Eve monitor and obtain ciphertexts?

Throughout my readings on cryptography, Eve is always assumed to have the capability to be a passive listener and obtain every message exchanged between two communicators. How can one demonstrate ...
2
votes
1answer
343 views

Kismet Output Shows 3 Possible Encryption Options, Which one?

Ran into an interesting situation with Kismet and Airmon-ng while observing a client wireless network. Basically, I'm observing the network using airmon-ng, and I have my BSSID and frequency set to ...
1
vote
1answer
699 views

Expiring Decryption Key

So, I'm just a programmer -- I don't know much about cryptography so bare with me and my lack of knowledge in this realm. But essentially, I'm wanting to cache data that could be potentially volatile ...
2
votes
1answer
264 views

Android: Are locally-stored encryption keys readable by attacker who gained root access?

i have a question: i'm trying to understand a specific point in android encryption. All the encryption keys are software based and are stored locally on the machine, so correct me if i'm wrong but ...
7
votes
2answers
2k views

Encrypting something with multiple keys such that k out of n keys are needed; what's it called?

I am trying to find information on how to encrypt something in such a way that there are n keys, and k of them are needed for decryption. However, I have been searching Google for half an hour but ...
5
votes
1answer
454 views

Does encrypting the same file twice with two different keys present a security risk?

Suppose you have a file that you wish to maintain two encrypted versions of, each version encrypted with its own (randomly generated, sufficiently long) key. The actual method of encryption is by ...
0
votes
1answer
221 views

Mac OS: keylogger vulnerability & FileVault 2

I'm configuring my mac and encrypting my disks with FileVault 2. As the boot disk is encrypted at startup I have to login via the EFI partition before the OS will boot. From my understanding, most ...
0
votes
2answers
336 views

Would multiple exposed bcrypt hashes of the same UUID v4 with random generated salt be too insecure?

I'm looking into implementing an ownership check on JSON objects and want to avoid going back to the database to ensure ownership of said object/record (i.e., to prevent a user from updating an ...
0
votes
2answers
899 views

Does using Bcrypt to encrypt credit card numbers satisfy PCI compliance?

I understand that using MD5 is not safe and is not PCI compliant. Does using BCrypt satisfy PCI compliance
4
votes
2answers
384 views

Totally secure public key distrubition

Public-key cryptography secures communications provided that you use pre-shared public-keys. The problem is how to share these public-keys while maintaining authenticity? How can we be sure that ...
1
vote
2answers
248 views

Can any asymmetric algorithms work with only a key-sized amount of randomness?

With 397 rolls of a fair 6-sided die (not my favorite use of time, but certainly not infeasible), I could generate more than 1024 random bits. Could I use those bits to generate a keypair that could ...
2
votes
1answer
517 views

Does any PXE/Full disk encryption password concept like this exist?

This question may just show a distinct misunderstanding of things on my part, and I apologize if it is, but I thought I'd put it out here as I don't know where else to ask. I've been thinking about ...
12
votes
1answer
2k views

TextSecure protocol

Is anyone aware of an analysis of the TextSecure protocol? https://whispersystems.org/blog/simplifying-otr-deniability/ https://github.com/WhisperSystems/TextSecure/wiki/Protocol It is a ...
0
votes
1answer
186 views

Corrupt password being pulled from wireshark data?

Hello everyone, I currently have a pcap file that contains an unencrypted Telnet session, and when I trace the TCP stream the password is in a format like so: pas...ord (please note ...
1
vote
3answers
1k views

Can I use an AP “Bridge” with password to imporve security over an open, unencrtyped WiFi signal?

I have access in my neighborhood to an open, unencrypted WiFi signal but I am leery of using it because of security reasons. I don't want to let my username, passwords or credit card numbers ...
2
votes
1answer
88 views

Is the following environment contained?

I would like to make sure that my working environment is contained (prevent data leaks meaning I don't want temp file or traces from files I have worked on). I am about to create a usb key with the ...
10
votes
4answers
2k views

Is it safe for GPG to compress all messages prior to encryption by default?

By default, GPG compresses text during encryption. Additionally, RFC 4880 says: 2.3. Compression OpenPGP implementations SHOULD compress the message after applying the signature but before ...
3
votes
4answers
536 views

Which encryption schemes have been designed without involvement from the NSA [closed]

What are the main stream crypto algorithms that have been designed without known involvement from the NSA? I know that twofish has been designed by Bruce Scheier, but which are the other ...
3
votes
1answer
441 views

Bitlocker lock drive on standby or switch users

Is possible to auto lock drive with bitlocker when the laptop go on standby or sleep mode? Or when the user is changed? I want the drive to be accesible only by one user.
1
vote
0answers
120 views

Techniques for web-user communication across an untrusted server

I'm designing a web-based notification framework (i.e. a user can subscribe to updates from a service or another user) where communication between users is encrypted. User-to-user communication on ...
1
vote
2answers
462 views

How to defeat CRIME, BREACH, TIME etc… server side (without sacrificing compression)

I am writing full-stack server side software and I have been researching CRIME attacks and it's relation to SPDY header compression as I am implementing the server side codecs for it at the moment. ...
3
votes
2answers
311 views

Is it true, that using symetric encryption, if attacker knows encrypted text, original message, and algorithm means he can calculate the secret?

I am a newbie in the security field, so sorry for the naive question. In my understanding, using symetric encryption, if attacker knows encrypted text, original message, and algorithm means he can ...
1
vote
1answer
506 views

MySQL AES Encryption - Is it good idea to store 3rd Party Auth Tokens using AES Encryption?

I need some advice on MySQL AES Encryption. I'm developing an application which connects to various 3rd-Party APIs and retrieves the Access Tokens for the application users. These Access Tokens are ...
1
vote
1answer
134 views

Oracle database privileges [closed]

I have a 10.2.0.5.0 Oracle Database and a list of users who i need to grant some privileges to (Mainly to generate reports and so on). I used impersonation, which means i created one Oracle user so ...
2
votes
1answer
657 views

Which products are affected by NSA's ability to crack pseudo-random-number generator Dual_EC_DRBG? [closed]

After reading this article about RSA advising its customers not to use the default random-number generator in its encryption products - amid fears spooks can easily crack data secured by the ...
0
votes
2answers
680 views

Storing email adress encrypted but deterministically

As part of an application I am developing, I am required to store user email adresses on a cloud DB. The email address is not required to be in plain text for the normal operation of the application. ...
7
votes
3answers
1k views

Does Google's SSL encryption for searches thwart NSA spying?

Given everything that is suspected about NSA (and GCHQ, DGSE, etc.) access to user data: Avoiding speculation, can and do we know whether Google's recent action to make all searches use SSL ...
3
votes
2answers
117 views

System for securely authenticating content acquisition

I'm having trouble designing a system for authenticated content from my site distributed by other people. I'm working in Ruby on Rails, but I don't think that at a theoretical level my question isn't ...
1
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0answers
240 views

Tools to perform benchmark of block/stream ciphers on Linux? [closed]

I would like to perform some benchmarking of different block and stream ciphers for general data (lossless and lossy data) encryption and decryption (with focus on power consumption). To get general ...
1
vote
1answer
1k views

Force browser to use higher security connection

How can I force my Chrome broswer (or even Firefox) to always use a higher security encryption?, for example 256bit (or more) encryption when using https. I guess it should be some flag to force the ...
0
votes
2answers
1k views

Algorithm to generate NTLMv2 Hash in PHP

I am trying to develop a PHP function to calculate NTLMv2 hash by providing server & client challenge, domain, account and password. The resulting hash appears to be not correct. Can someone ...
1
vote
0answers
469 views

Configure Asterisk for lan with SRTP enabled SipDroid [closed]

I want to have a secured call over internet between two android phones. I have found SipDroid which is an open source SIP client for Android. And also I have followed this to install Asterisk, Dahdi ...
1
vote
2answers
222 views

Main requirements to secure my Application in any database related features

I have an application which is hosted on a windows server on which an SQL DB exists. This server communicates with the clients and agents installed on host PCs through TCP/IP and SSL connections. I'm ...
-1
votes
1answer
223 views

Permutation in Block Ciphers

I was reading some e-books to understand the basics of block ciphers and how it works in AES. As i understood, Permutation plays a big part in AES and Block Ciphers, Here is what i understood by ...
-1
votes
2answers
126 views

Pad encryption against eavesdropping

In regards to security, Why is one-time pad encryption unconditionally secure against eavesdropping? Also, why does the triple DES use an Encryption-Decryption-Encryption combination rather than an ...
0
votes
1answer
147 views

How to fetch and update all my friend's keys? [closed]

Where can I upload a list of my friends and get a list of their keys found on keyservers? Here are some key servers: http://keyserver.ubuntu.com:11371/ http://pgp.mit.edu/ ...
3
votes
4answers
536 views

What are the features of Dual EC DRBG that are lost when using a different cipher?

Due to a potential NSA backdoor, the NIST is now recommending that implementor no longer use ECC-based PRNG Dual EC DRBG. (As described in Wired.com) this PRNG has certain features such as: ...
1
vote
3answers
193 views

Reading to Decide on a career switch [duplicate]

I have a strategy consulting and sales background, but what I read about IT and IT Security sounds fascinating as an outsider. I'm considering a career switch, but would need to know quite a bit more. ...
-3
votes
2answers
983 views

How to tell what encryption is being used [closed]

How do you tell encryption algorithm used by reading its output? Here is the one I am trying to figure out Åbd$ý ...
3
votes
2answers
2k views

Using multiple keyfiles in truecrypt

I have a truecrypt container who's main password is 20+ characters long. I don't know if the keyfiles are still necessary for further improving the security. But anyway, I have folder of some .jpeg ...
2
votes
2answers
2k views

Encryption - which are/aren't NSA backdoored [closed]

I prefer bcrypt because it uses a lot of "power" to decrypt. But which encryption can i use that is most likely safe for NSA (which knows a lot of backdoors) and is relatively slow to decrypt. I ...
1
vote
1answer
497 views

Does RSA encryption always pad small amounts of data to some larger size?

If I encrypt 160 bits (20 bytes) of data using an RSA 1024 private key, will the result always be 128 bytes? This seems to be the case in my experiements, but I want to be sure. For example, ...
5
votes
2answers
2k views

Website: Pre-Shared-Key Authentication

We have this web-application with high valuable (business) data. All communication is encrypted through TLS/SSL. While I consider this a really safe protocol, it can still be compromised if someone ...
0
votes
2answers
310 views

Double encryption with different keys [duplicate]

I have a software development kit which packages the data for the finished program in a series of LZMA packages. I want to ensure that my software is the only program that can read the packages, even ...
1
vote
1answer
270 views

Is there symmetric encryption like AES or Camelia with keys longer than 256 bits?

I am wondering if is there any (secure!) cipher like AES or Camelia with keys longer than 256 bits (and offering higher security than 256 bits). I have not found anything except ...
1
vote
1answer
2k views

ECC Brainpool Standard Curves and Curve Generation with Bouncy Castle which seed to use?

I want to implement a ECC Key Agreement with a Brainpool curve brainpoolP512r1 or brainpoolP512t1. I'm not clear about whichseed value to use (and how). In this document ...
11
votes
2answers
3k views

How does a weakness in a random number generator lead to a compromise of the entire cryptographic process?

In the news, there are several articles (here, here, and the technical point of view) which have to do with a weakness in a random number generator. The question is somewhat twofold. What symptoms do ...
2
votes
1answer
4k views

What is a stub?

Would someone please explain in depth what a stub is? I understand it as a file created by a crypter to keep a program encrypted and undetectable by anti-virus software. It is attached to the ...