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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689 views

Two step encryption

Consider the following user case: I have some sensitive data (eg: credit card number) I encrypt this data and store it in the database Now I want to send this data to a user X, but I don't want to: ...
5
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5answers
785 views

HOWTO : Email encryption in a browser

I have read about encryption and I think it's a good idea for me to encrypt my email. I run ubuntu 12.10 and use Firefox for browsing. In my quest for learning how to use gmail/hotmail to send and ...
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3answers
17k views

Choosing a session ID algorithm for a client-server relationship

I am developing an application which has a client-server relationship, and I am having trouble deciding on the algorithm by which the session identifier is determined. My goal is to restrict ...
2
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4answers
1k views

Code, Data and Passwd encrypted? sqlplus $USER/$PASSWORD@$ORACLE_REMOTE_SID

Lots of our *NIX scripts use "sqlplus $USER/$PASSWORD@$ORACLE_REMOTE_SID" I know that not good to have clear text password in scripts (there is no alternative at the moment). But question is the ...
8
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6answers
790 views

Security of email [duplicate]

Possible Duplicate: How commonly are SSL/TLS or S/MIME used by e-mail providers? Say, Alice uses gmail and Bob uses hotmail. Alice wants to send an email to Bob. Alice goes to gmail website ...
5
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2answers
6k views

How effectively can ISPs detect illegal file sharing?

Recently the USA passed a law requiring ISPs to spy on their customers' internet connections to check for illegal file sharing. I assume that they would do this by sniffing packets, but doesn't this ...
2
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1answer
267 views

Design of Initialisation Vector

I understand that an IV (initialisation vector) should be both unique and unpredictable, but I have found little guidance as to which is most important. For an AES cipher I have a block size of 128 ...
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5answers
676 views

Does shuffling a hashed password increase its security?

I am making a web app and I'm now stuck on making the login secure. I'm thinking of adding a salt to a user-inputted password and then hash it. (md5 or sha for example) and then I will reshuffle the ...
1
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1answer
231 views

How safe is WSIT username authentication with symmetric key?

I have an ajax-ws web service (exposed via glassfish) that uses username authentication with a symmetric key to encrypt and authenticate clients(link). How secure is this mechanism? Is this enough to ...
3
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1answer
252 views

Can we use a public key scheme for performing cryptographic commitment

Is it possible to use a public key scheme such as DSA as a commitment scheme? Are there any problems with doing this?
5
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1answer
500 views

API Design Model - Client Side Encryption

I'm currently designing a API Model to use. A user will have a 'secret_api_key' and a 'public_api_key'. They will send a request to my server with the public key, the form data, and then a hash. The ...
2
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1answer
342 views

White-Box Cryptography Questions and References

I have recently started reading about White-Box Cryptography and looking at references/papers/web sites. A have a few questions I was hoping to get guidance on. As far as I can tell, WBC has ...
2
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1answer
311 views

What security risks are involved with sending data over the internal network on Rackspace Cloud servers?

What are the risks involved with sending unencrypted data over the internal network with Rackspace Cloud Servers? Assume the interfaces use iptables to filter IPs and ports so they only accept data ...
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3answers
2k views

How secure is aSSL (javascript)? Does it effectively mimic SSL?

Some of you may be familiar with the aSSL project, which uses AJAX/PHP to mimic the SSL protocol. It uses RSA 512 or 1024 for the keys, and AES for the actual data. It looks impressive to me in ...
18
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6answers
3k views

Principle of asymmetric algorithm in plain english

I was giving a presentation to my colleagues about cryptography basics in which I explained about asymmetric algorithm and its use. One of the common question from the audience about asymmetric ...
15
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5answers
2k views

Securing a laptop against attacks (article)

I came across this article when looking for ways of hardening my laptop, and this guide seemed extremely thorough. It is perhaps overly paranoid, but it will be good to have a guide I can trust should ...
2
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1answer
4k views

Is Google's Hangout using encrypted communication?

I am trying to use Google's Hangout as alternative to WebEx for sharing screen. But not sure if it is safe.
5
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1answer
366 views

Most efficient key algorithm for a TLS server key?

Let's assume I want to setup a HTTPS service on a modern-but-no-so-speedy x86 server without any form of hardware cryptographic accelerator. Which key algorithm should I choose for the server key in ...
5
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2answers
916 views

Encryption key storage

I recently inherited an in-house built key storage system. The company stores credit card data in two database servers which are AES encrypted. The keys reside in a separate system that is located in ...
2
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3answers
1k 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 ...
9
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3answers
1k 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 ...
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2answers
259 views

Can someone figure out the encryption method?

Is there a way to decrypt a database if I know the encrypted and decrypted state of the data? We have old software at work (VB) that needs rewriting, problem is that the database is encrypted. I can ...
3
votes
2answers
268 views

Secure login across two web apps

I have an requirement to implement cross-domain login for two web apps (APP1 and APP2) so that a user can access APP2 once they have logged into APP1. APP2 needs to know an ID of the user who is ...
2
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3answers
2k views

Key Exchange using PKI

I'm new to the field of cryptography and trying out a sample program to understand PKI key exchange mechanism. I tried creating a self signed certificate using openssl openssl req -x509 -nodes -...
7
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1answer
320 views

Encryption in an embeddded system

After accepting an answer to my previous question, I am beginning to have doubts. I want to updating pricing information in vending machines by inserting an SD card with new pricing. I have to ...
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2answers
494 views

Seeking lightweight encryption - shareable between Delphi & C

I want to encrypt a text file in Delphi & decrypt it, line by line, in C on an embedded system which does not have much RAM (so, only one line in RAM at a time). FOSS must be available for both ...
3
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1answer
765 views

Can I encrypt a file incrementally?

Is there any way to encrypt a file incrementally? The problem is that I receive a file a chunk at a time via Internet (it's a client-server application and I send byte arrays via a WCF service) and I ...
2
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1answer
2k views

What would be the scenario if P = NP for RSA algorithm?

Suppose I am using RSA for my security system. Now someone discovers find a polynomial time algorithm for RSA. Then what measure should one that such that RSA never breaks. Maybe large number of used ...
22
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2answers
16k views

Strength of WEP, WPA and WPA 2 PSK

I know there are three method for wifi security. What are the relative strengths of the password encryption in WEP, WPA and WPA2 PSK?
6
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1answer
977 views

Android and AES side channel attacks

I am working on a project that will involve symmetric AES 128 bit encrypted communication between an Android application and a bluetooth device. Are there any public AES libraries available for ...
2
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2answers
1k views

Determine encoding/hashing methods used based on knowing the input and output only?

If I know the initial value of a string and the resulting hash but have no access to the system that produces the output, how can I determine what has actually occurred so I can reproduce the hashing ...
5
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2answers
2k views

How to login and encrypt data with the same password/key

I've made a "vault" web app in PHP for storing passwords, credit card numbers, etc. It's mostly just for myself, but I'm practicing building it with multiple users in mind. I use two way encryption to ...
10
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3answers
2k views

How can I encrypt a file with .NET and have the same file size of the original file?

I'm using .NET and I've written an awesome routine (xD) that encrypts and decrypts a file using AES256 CBC. It works perfectly, but now they told me that the encrypted file must be of the same size of ...
7
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1answer
129 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 ...
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2answers
264 views

Certificate security in intranet environment?

We have this topology in our company: A new rule says that each document being sent by Outlook should be encrypted. We decided using PGP. We already have a certificate (self-signed). The problem ...
4
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1answer
477 views

Is OpenPGP encryption a valid replacement for SSL when passing messages?

I am writing an application that occasionally needs to transmit larger messages to other servers on the internet without allowing people to snoop on the traffic. The normal way to handle this is to ...
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0answers
155 views

Why not buy cheap SSL certificates? [duplicate]

Possible Duplicate: Is there any technical security reason not to buy the cheapest SSL certificate you can find? The comparison in Godaddy's website, makes it clear: they're just cheaper than ...
2
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3answers
378 views

Password Security: Encrypting salt [duplicate]

Possible Duplicate: Password Hashing add salt + pepper or is salt enough? I'm new to security and trying to understand why encrypting or hiding a salt is not considered useful. I've read the ...
4
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3answers
2k views

rsa encrypted hash == rsa signature

$ echo -n "1327943823" > test_ok.txt $ openssl dgst -sha1 -binary -out test_ok.sha1 test_ok.txt $ echo "GURbsl4CFPCG83RCZxsEpoRleXicXQhH1OC4Fk77b7EMj2g8aHUhD/L+sm ...
3
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1answer
3k views

What are the Netscape Cert Type attributes? Why/when are they needed?

What are the Netscape Cert Type attributes in a X.509 Certificate and how are they different with the X509v3 extensions? Example: There is the Client/Server Extended Key Usage (X.509) but there is ...
3
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4answers
156 views

Strong authentication over insecure links

Let's begin by assuming that we're operating in either a corporate or Governmental environment where SSL man-in-the-middle interceptions are a given and that *all* traffic on the network between the ...
6
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2answers
816 views

What risks does WPA carry?

A family member of mine would like to be able to play old PSP games online. Unfortunately the device does not support WPA2, and my network is strictly WPA2 AES secured. What are the risks involved in ...
2
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1answer
279 views

Seeding GPG keygen with a hashed secret [duplicate]

Possible Duplicate: Tool for public key cryptography where password is the private key? I was wondering if you guys could clue me in to potential problems with using a hashed password as the ...
6
votes
3answers
345 views

How much added security do I really get with a longer key size?

Imagine I have a cipher which supports keys of 128, 192 or 256 bits. Suppose that there are no vulnerabilities in the cipher regardless of key length. I'm going to use it to encrypt something, and I'...
14
votes
6answers
2k views

Why not RSA-encrypt the entire document?

I have recently learned of a way for person B to verify that a document sent from person A is indeed from person A. Person A gives Person B his public RSA key. This must be done reliably. Person A ...
18
votes
3answers
16k views

How to encrypt database connection credentials on a web server?

OWASP advise against storing DB credentials in plain text: https://www.owasp.org/index.php/Password_in_Configuration_File However, they don't provide suggestions of how to encrypt the DB access ...
2
votes
1answer
285 views

Password checking in the context of symmetric encryption

It is my understanding that block ciphers like AES don't have any built-in mechanisms to verify data integrity upon decryption, although some modes of operation might provide that. I played around ...
2
votes
1answer
190 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 ...
0
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2answers
268 views

Analyzing SSL encryption

I have to analyze SSL encryption in my test network and want to prove the transported data is encrypted. What methods can I use to prove encryption is in place?
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3answers
643 views

Should I use a Firefox master password or NTFS encrypt my profile?

As a follow-up to another question, is the encryption via Firefox' master password more secure than simply NTFS encrypting the profile folder? I.e. is there a convincing reason to add the ...