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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406 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 ...
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1answer
213 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
17k views

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
951 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
906 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
votes
1answer
852 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
893 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, ...
3
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2answers
450 views

Is it possible to automate use of passphrase-encrypted private keys?

Suppose I have a public/private keypair, which I would like to use to serve HTTPS from a webserver. The part I'm worried about is this: the private key is encrypted with a passphrase, so that if an ...
-3
votes
1answer
199 views

US Export Laws (Encryption Cloud Service) [closed]

Okay - so I have been extensively looking into US export/import laws relating to encryption software (5D992), however I have a few questions about the laws and their applicability. So, the laws ...
16
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5answers
10k views

SSL/TLS - Distinction between self-signed cert and self-signed CA, and other questions?

I have a small personal website which I wish to serve securely over HTTPS. At the moment I do not wish to use a third party CA to sign my certs. I was reading this document on generating a self-signed ...
3
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1answer
5k views

How to encrypt a short string to a short ciphertext using an asymmetric encryption?

I am using RSA to encrypt some text, so my system has already generated private and public keys. These keys I would like to use to encrypt/decrypt a short text (16 chars). The main condition is: ...
8
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3answers
1k views

Is it possible to prove which public key was used to encrypt a message?

Pretty much the title: If Alice sends a message to Bob that she encrypts with Bob's public key, is it possible for Eve to prove that the ciphertext was encrypted with Bob's public key, that the ...
5
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6answers
2k views

Tracking unique web site visits without logging IP addresses

On Monday, some IP address xxx.xxx.xxx.xxx visits my site. I log it. On Tuesday, another IP address yyy.yyy.yyy.yyy visits my site. I log it. If the two IP addresses are equal, I throw out the ...
5
votes
2answers
141 views

Serving data from an encrypted database over an encrypted connection

There is encrypted data in the database (asymmetric FYI). It is to be viewed as decrypted on the website. The data can be sent to the client as encrypted to be decrypted on the client's computer, or ...
3
votes
1answer
214 views

Certificate Hostname Mismatches - Why do they matter?

So, I am implementing some X509 certificates in a backend service where we have our own self-signing process to allow different nodes (out of our control) to receive our blessing (as a CA of sorts). ...
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votes
1answer
821 views

Encrypton method that would encrypt alphanumeric data to alphanumeric data [closed]

I need efficient way(possibly as strong as AES or AES itself) to enrypt (only) aplhanumeric data and get out only alphanumeric data, using some known library (i don't want and intend to implement AES ...
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1answer
344 views

Development of asymmetric encryption algorithm? [closed]

I am planning to develop (make some minor changes) to asymmetric encryption (i.e. RSA). Any suggestions please?
3
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3answers
2k views

SSL vs Encryption

I am working on creating an android mobile application which needs to connect to a server from time to time. The application makes use of sensitive data which I would not like to get into the wrong ...
-5
votes
1answer
383 views

Can I develop an SSH client for iPad in Sweden and sell it in Apple App Store? [closed]

I wonder, if I am allowed to develop an SSH client for distribution through Apple App Store without breaking any export regulations? I don't really know much about the encryption algorithm. Below is a ...
8
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1answer
2k views

What are the benefits and drawbacks of the HTML5 Keygen element?

As of January 2013, what are the potential benefits and drawbacks of the HTML5 Keygen element?
9
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1answer
2k views

HKDF and key stretching

I thought that all key derivation functions would do a key stretching phase, by iterating some kind of process. But I can't see that process in HKDF. HKDF doesn't do key strengthening? If I have a ...
13
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3answers
601 views

Can I use the same password both for SRP and for client-side encryption?

Suppose a less-than-trusted server is used to store users' confidential data (encrypted at the client side), and both tasks - authentication and encryption/decryption - should be doable with a single ...
15
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2answers
3k views

Security of running openpgp.js in a browser with the private key in HTML5 localStorage

If I were to write a web application using openpgp.js (http://openpgpjs.org/) for creating PGP encrypted/signed messages and if I stored the user's private key in localStorage, would this be ...
6
votes
2answers
233 views

Should I test my SSL certificate for “RSA Shared Primes” before using it?

There are several papers from 2012 that say it's possible to factor several moduli by factoring shared primes. The link above includes python sourcecode to verify and test for this fact. Given this ...
3
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1answer
456 views

Why should I pay for an email S/MIME certificate?

There are quite a few SSL certificate companies out there that offer free email S/MIME certificates. There are also paid versions as well. I need about 6 email certificates for some company email ...
18
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3answers
969 views

Can a nation-state adversary perform a MITM attack by compelling a CA to issue them with fake certs?

As I understand it, with any encryption system based on a trust chain / CAs (eg SSL, TLS, S/MIME), it would be possible for a nation-state adversary (such as the NSA) to compel the CA to issue them ...
2
votes
1answer
253 views

AES + CBC to encrypt individual local files, fixed IV?

I am using AES and CBC to encrypt a local files separately. I don't plan to transmit them over any network. What are the risks of using a fixed IV for my encrypting application? The only problem I ...
2
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0answers
64 views

What flexibility does a “Third party gamma” offer to U-Prove deployment?

The U-Prove SDK has the following comment: (link) // 1: CA-RA split (a party trusted by the issuer provides the gamma value) Given that the Gamma value (if provided) overrides the Attributes value, ...
14
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2answers
1k views

Can a Firefox add-on or plug-in access the user's websites' saved passwords in decrypted mode?

Going deeper into the previous question on Firefox plugins and add-ons malware risks: Could a Firefox add-on potentially decode and capture the encrypted websites' passwords saved in the browser?
24
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9answers
9k views

Is encryption in HTTPS done by the browser or by the system?

This may be a common sense question, but I am not able to find any documentation on this after searching on google for a long time When browser makes a HTTPs request, does it encrypt the data then ...
33
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1answer
7k views

Why does AES encryption take more time than decryption?

While I was studying the time consumed by some methods I found that encryption take more time than decryption. Is this right? I am using AES (the same steps will be taken during the enc and dec)
2
votes
1answer
5k views

How can I decrypt traffic on a WEP encrypted network?

Let's say that I am connected to a WEP Access Point and I want to sniff all wireless traffic inside that network. How can I decrypt the traffic even though I don't have the cryptographic key? I found ...
6
votes
3answers
1k views

Safe implementation of sharing encryption secrets (username, password) in the cloud

I'm building a multi-tenant (cloud) environment that needs to push out (or make available for download) configuration files for agents (background services) that receive this information. One of the ...
1
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0answers
94 views

Is this any recognizable encoding or cipher? [closed]

I've been watching the Marble Hornets videos on YouTube (basically, an independent film series about a group of kids chased by the "Slender Man"), and in this video I saw something interesting. ...
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2answers
295 views

IPTable Security between two servers

Is using IPTables to only allow traffic between two servers considered an acceptable practice? For example TCP traffic on a defined port. I realize this is referred to as an ACL but how secure is ...
3
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2answers
115 views

How to ensure two messages are from the same party

I need to verify that two messages, that came over distinct channels, come from the same origin: without knowing anything about the origin beforehand the channels are one-way, only one message may ...
3
votes
2answers
853 views

How safe is a PGP private key that has “escaped”, but without its password?

Assuming your PGP private key is protected with a password, and it "escapes", but the password does not, how worried should you be? Obviously in the real world, you would immediately revoke the key ...
0
votes
1answer
83 views

Performance issues while applying encryption at host or guest level?

One of the security expert here suggested me to apply encryption at guest(virtual machine) level rather than applying at host level with good reason. Before applying that I want to know what can be ...
0
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1answer
196 views

Which one is best, host or guest encryption?

Can anyone please tell me which option is better, I mean whether I should encrypt my data at virtual machine level or guest level in cloud? I tried to investigate it but did not find best solution so ...
8
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1answer
2k views

Build a secure channel without SSL/TLS

I'm looking at possible options to build a secure channel between multiple embedded devices with limited cryptography capabilities and an HTTP server (It could be some sort of web service). 1. ...
21
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2answers
5k views

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?
4
votes
1answer
3k views

Credit card data security - hashing, truncation and encryption

A question with a similar title has been asked before, but it doesn't answer my specific question here. PCI DSS permits storage of truncated and encrypted data, or hashed and encrypted data. It ...
2
votes
1answer
616 views

How to manage passwords in a multi-tenant surrounding?

I am building a multi-tenant application in a shared database model. I would like to encrypt sensitive data so that only a particular tenant could have access to his data. What is the best mode to ...
1
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1answer
2k views

Man-in-the-middle attack over an encrypted channel

I learned recently about man-in-the-middle attacks and came up with this question. Let's say we have two computers who try to communicate over the network. Each computer has an encryptor and a ...
7
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1answer
2k views

Working out how to decrypt encrypted string when knowing the plain text

I have access to a system which I have been asked to create a data export routine for. However, the address details are encrypted and the original sourcecode/password are lost. However, I am able to ...
7
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3answers
914 views

How to fuzz proprietary protocol over SSL?

I'm doing vulnerability research on a client/server architecture that uses a custom proprietary protocol sent over SSL (port 443). I need to be able to intercept the traffic, and be able to view it in ...
13
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4answers
6k views

Why does PGP use symmetric encryption and RSA?

Looking into the details of Pretty Good Privacy, I'm confused as to the reasoning behind encrypting the message with a session key and the key with the recipient's public key via RSA. I fail to see ...