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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4answers
439 views

Authenticate user without knowing their password

I'm working on a project where each each user will have a public/private RSA key-pair. Users will be able to send encrypted messages to each other using the each target user's public key so that only ...
1
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1answer
56 views

Securing an OAuth / OpenID Connect identity in a cookie for easy login

I have a website that uses Azure Active Directory or Google+ for logging in. I go through an OAuth2 login flow, and the users email along with their tokens are returned to me by their identity ...
1
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1answer
68 views

Problem with common factor in RSA [duplicate]

In the RSA key generation steps, what if two entities select a common factor to generate n (i.e. p*q1=n1 and p*q2=n2) resulting in gcd(n1,n2) <> 1 ? This will lead to a problem that everyone ...
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1answer
66 views

Is it safe to store important data in an encrypted access token?

Is it safe to store important data in an encrypted access token? For example, instead of storing access tokens in a database, not storing them at all and putting their associated data into them before ...
10
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4answers
3k views

How do I encrypt the source and destination IP address, along with various parts of an email?

If the subject makes no sense to you, that's fine, it makes no sense to me. I've been tasked with securing emails sent from some devices, and I'm looking for advice on intelligent questions to ask to ...
9
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7answers
38k views

How can I determine the encryption strength of an SSL connection

If I've connected to a https url, how can I determine the cipher strength of the connection? My understanding is that after the asymmetric public-key handshake the information is encrypted using a ...
0
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2answers
145 views

With RSA, can one ensure that two entities will not have the same private key?

With the RSA encryption algorithm, is there any guarantee that two different entities will not be given the same private keys?
2
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2answers
82 views

Securing commands

For a project I'm working on, I need to securely send commands between servers. These commands should not be able to be altered, and there should be some security about not being able to just keep ...
21
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6answers
1k views

How to secure a WiFi network?

What do I have to do to secure a WiFi network? Is there any best practices? I have been recommended to use WPA2 encryption on the router, is that enough? What can I do to improve the security even ...
0
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3answers
125 views

Can you have Secure encryption with a backdoor, and still be secure?

Is it possible to have an encryption algorithm/implementation that has a "backdoor", that also wouldn't introduce flaws into the encryption? For instance, if you have a master password, once that ...
1
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1answer
112 views

Secure backup on online Cloudstorage

i own a small private server (@home) with all necessary features for my backup purposes (Owncloud, SVN, GIT). My target now is to ensure the safety of my data in emergency cases like fire/flood. For ...
2
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1answer
179 views

Storing a user's password in a retrievable manner

I currently store my users passwords as PBKDF2 hashes, for the authentication part of my web application. Each user also has their own private key and public key (also stored in their user profile in ...
3
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2answers
101 views

Key Size vs. Block Size: In Practice

I've seen a lot of confusion between encryption key size and block size. I feel like I completely understand the difference between the two, no need to explain what they are. But it's when put in ...
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3answers
78 views

Can AES encryption prevent modifying bits in a wireless protocol?

I'm building an application with NFC which is a wireless communication protocol. An attacker can modify bits in a wireless communication protocol. I want to prevent this. I know we can't prevent an ...
1
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0answers
134 views

Encrypt in C# program, Decrypt in android application By RSA Keys

I used RSA Encryption for sending message between Server and client. The server program implemented by C# and the Client is an android application. I want to know is it possible a message that ...
2
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1answer
77 views

The most trusted hard problem [closed]

Is there a mathematical formalism to rank the hardness of the hard problems? In particular I am referring to the sort of hard problems that are typically used in cypher system; such as factorization ...
5
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6answers
15k views

Is Windows BitLocker secure?

Naturally I feel that I have to ask this question, since it's a built-in feature in Windows. Let's say someone has physical access to my PC, is there an easy way for them to access a BitLocker ...
6
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1answer
4k views

Will double encryption increase the security of cipher vs bruteforce?

Assume I have a function encrypt(mes,key) where mes is the message, and key is the key. The length of key is 64 bits. Last but not least: assume the only way to crack my cipher is a brute-force ...
1
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0answers
60 views

Is it possible to encrypt Word Docs with something other than default?

AES 128-bit advanced encryption is fairly simple to break and was wondering if there was any way to use a more secure one? And if so - any suggestions?
2
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1answer
169 views

Is knowing the decrypted and encrypted data enough to find the key?

Let's say an attacker knows the encrypted content, the decrypted content and the algorithm used: can he get the key that was used to encrypt the content or does it make it easier to find the key out? ...
0
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1answer
102 views

How to decode/decrypt strings of text [closed]

So I'm trying to decrypt/decode some text strings. I don't believe they're hashes because they vary in length too much and the software they are used for is able to easily decode them and display them ...
1
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1answer
44 views

How can I hide proprietary elements of test data in tests that are automatically run?

I am writing automated tests for a web application that will be run periodically over night, and I am running into a moderate security issue. In order to make the tests thorough, I am hoping to ...
1
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1answer
126 views

Mapping of plaintext and ciphertext in DES

The plain text and the cipher text have a one to one mapping. Given a pair of those, can there be multiple keys used to generate the same pair? Or can a particular plain text - cipher text mapping be ...
22
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2answers
12k 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 ...
1
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4answers
314 views

Is e-mail sent from a Gmail address to another Gmail address encrypted?

Gmail provides an SSL connection and also encrypts the entire session by default. But if you send a mail, once it leaves gmails servers, it can be read at any point on the internet. But what about ...
3
votes
1answer
459 views

How resistant is the iPhone encryption against brute-force attacks?

I just read the following paragraph in an article from the New York Times about Apple encrypting iPhones by default): Breaking the code, according to an Apple technical guide, could take “more ...
0
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3answers
113 views

Is is necessary to encrypt the message digest?

In symmetric key settings, in order to provide the message integrity, we compute the hash of the message. The message along with the message digest is then encrypted. Is it necessary to encrypt the ...
2
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2answers
150 views

Does a self-signed certificate offer more protection than a public key?

I'm having a hard time finding the practical benefits of transmitting a self-signed certificate over simply a public key. I understand that a self-signed certificate proves the integrity of the public ...
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0answers
64 views

Secure self-concealing symmetric encryption (non-verifiable decryption)?

From what I observed using standard encryption tools such as OpenSSH and GPG, the decryption only succeeds when the correct password/key is provided (or at most a few others, in case of collision). ...
0
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2answers
196 views

What does 2^77.1 calls presented in a SHA1 attack mean?

Regarding the SHA 1 deprecation, I found this information here: http://blogs.technet.com/b/srd/archive/2013/11/12/security-advisory-2880823-recommendation-to-discontinue-use-of-sha-1.aspx I know ...
10
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4answers
2k views

Location to store an encryption key

I'm building a secure system which stores messages on a server in a Postgresql database. The messages are stored encrypted with PHP's openssl_encrypt() function with the AES-256-CBC method. At the ...
3
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1answer
5k views

What needs to be encrypted for FIPS 140-2 compliance?

We're developing a Client/Server C# .NET application that needs to be FIPS compliant.Im reading a lot about FIPS online, but am having a bit of difficulty determining the difference between the ...
1
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3answers
215 views

Is a Diffie Hellman Ephemeral key good material for being used as a symmetric cipher algorithm key?

I am designing a secure protocol (for academic/learning purposes) and I am at the point where I need to (re)design the key exchange step. In my previous implementation, I used to rely on RSA to ...
2
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3answers
116 views

AES Key Management / How To Swap Encryption Key

I'm currently using AES 256 for the encryption of my web application and the security policy context specifies that the encryption key must be replaced once every few months. When that happens what ...
2
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2answers
110 views

Does adding multiple recipients to an encrypted message decrease security?

Let's say you want to send the same GPG/OpenPGP encrypted message to 50+ recipients. Assuming everyone you send to is trusted, and there is no risk of any recipient leaking their secret key, is ...
5
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6answers
9k views

Mysql - two-way encryption of sensitive data (email addresses) outside of Apache, PHP and MySQL

We store user email addresses in our database, like many other websites. While we do take pride in the security measures in place, sometimes "just enough" is just not enough. We've begun looking into ...
0
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0answers
28 views

L2tp protocol security

do l2tp protocol is secure enough to use in unsafe home network ? protection from man in the middle ? i having a problems install openvpn in linux you think following that guide will offer me ...
18
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5answers
1k views

Why is security through obscurity not a good option for encryption? [duplicate]

I feel like there must be a simple explanation, but I've been looking around haven't found any wholesome answers. Take for example my name is Alice and my best friend Bob and we want to communicate ...
3
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1answer
95 views

Does encrypting a setting in web.config actually provide security?

Does encrypting a value in the web.config file actually provide any real protection? It seems to me that any web app can read that setting. Yes that's more work than just reading the web.config file, ...
11
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2answers
7k views

Decrypting TLS in Wireshark when using DHE_RSA ciphersuites

How can I decrypt TLS messages when an ephemeral Diffie-Hellman ciphersuite is used? I am able to expose the premaster secret and master secret from the SSL Client. Using that, how to decrypt the ...
0
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1answer
100 views

How can I safely include the encryption key in the encrypted file?

I am encrypting text files using AES256 (no particular reason, that can easily be changed). Before granting access to a file, I need to verify if a party knows the correct key, but without necessarily ...
1
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3answers
511 views

Java AES encryption output length

I am trying to encrypt few database columns (string values) using Java AES algorithm. This is to protect certain sensitive data. For some users these data should decrypted. In Java AES encryption, if ...
2
votes
0answers
178 views

Some http requests are not send encrypted by vpn! Why?

I subscribed to a VPN service recently, and installed wireshark to take a look at the traffic sent from my computer. Practically all of it goes through UDP protocol, encrypted. But there are two HTTP ...
0
votes
2answers
170 views

Can we hide a constant hashed key used for AES encryption of a password?

Are there any methods in java to hide a constant hashed key which is embedded in a class? FYI, the key is used to AES encrypt a password used to authenticate a Web Service which would only take a ...
9
votes
5answers
14k views

Can Skype chat be protected from snooping? Are there safe alternatives?

I use Skype a lot. With all of my clients, staff, contractors and friends, however, the acquisition by Microsoft worries me, as two of my clients are direct MS competitors, and I often work on long ...
0
votes
5answers
883 views

What voip client support manual encryption?

In pidgin there is a plugin that we can use to encrypt our messages in chat windows .. Is there anything simular for voip (pc to pc) ? any client that support manual encryption for voice data?(linux)
1
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1answer
113 views

Efficacy of self-made ransomware protection

I was recently wondering about how to circumvent malware such as the infamous Cryptolocker a while back and was wondering about the efficacy of having a set of files with known content in a known ...
3
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2answers
68 views

Any advice on how to assure patients that a medical facility is well protected against identity theft?

My apologies if this question has been asked before. How does a medical practice assure patients that the practice follows excellent computer security practices? Conversely, how does a patient find ...
13
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3answers
1k views

Trying to understand why signatures in root certs “are not used”?

Taken from here: Don't worry if the root certificate uses SHA1; signatures on roots are not used (and Chrome won't warn about them. Why are the signatures not used? Are not root certificates ...
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1answer
84 views

What is the algorithm of bcrypt? [closed]

In many places I heard that people recommend to use the bcrypt algorithm to save passwords into database while creating web applications.I want to know what is the algorithm used to bcrypt a password ...