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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Why is Chrome saying that “TLS_RSA_WITH_AES_128_CBC_SHA (0x2f)” is an obsolete cipher suite?

When I go to this site, Chrome Version 44.0.2403.89 is connecting to the server with TLS_RSA_WITH_AES_128_CBC_SHA (0x2f), and it states that this is an "obsolete cipher suite". For what reason is it ...
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1answer
71 views

Secure Software Architecture

I am designing a software architecture and i need some suggestion and clarification on few issues. This will be a server side RESTfull API for accessing data and multiple mobile/desktop client to ...
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0answers
47 views

Is there anything to worry about — worth putting security on a simple test site?

So I want to make a site, this site won't have users (so no one but me will be able to post to the site) or anything it will just echo out items from Mysql like title and text-body I was wondering if ...
2
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2answers
61 views

Authenticated encryption (Symmetric encryption) for .NET applications [closed]

Is there an implementation of Authenticated encryption for .NET applications? The AES API from .NET does not include mode such as GCM. In the documentation, I can only see insecure modes (ECB, CBC, ...
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2answers
68 views

Content on a usb flash drive available for a limited time [closed]

I need to distribute some content on a USB flash drive. This content should be available for a limited time only. I am looking for some approach to achieve above. So far I do not have information ...
4
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1answer
161 views

Securing administration network

We would like to secure our administration network from advanced persistant threats and also from rogue administrators. I have already read the best practices from SANS Institute, NSA or other guides. ...
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2answers
106 views

Could I ever be legally required to decrpyt user information? [closed]

Suppose I host some web app which stores information about its users. In the interest of confidentiality, that information is stored in an encrypted format. Under what circumstances could a legal ...
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1answer
46 views

Key derivation inside secure container of HSM

I have to implement custom key derivation function which basically works as follows: I have encryption key K in secure container of HSM. K can't be exported and the only way how to use it is through ...
0
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1answer
84 views

I need to transfer user's private key (RSA) to my App. Is file sharing a good solution?

I've asked a similar question here earlier iOS: Is it ok to store a RSA private key (use to decrypt text) in your application document directory? However, the person recommend me to use keychain ...
3
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1answer
53 views

Cipher usage by end users and browsers

How do I check in apache logs as to what cipher end users / browsers are using ? Are there other tools to achieve the same to get a result in percentage ? related link: How can I determine the ...
3
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4answers
146 views

How safe is password based key derivation in the case of long password?

I am encrypting files inside a device and store it. So I need to maintain the same key throughout the life cycle of the device. For key derivation I use EVP_bytestokey() of OpenSSL. The problem in ...
12
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6answers
5k views

Is (safe) encryption over compromised line impossible?

I realize something like this would be the holy grail of communications security and have never heard anything to suggest it has been done. Am just wondering. A lot of mathematicians and computer ...
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1answer
43 views

A collection of tests and demos for security headers and TLS configurations [closed]

There are (or have been) various websites designed to educate and provide examples on good / bad configurations of security headers and TLS configurations (e.g. https://badssl.com/) I want to build a ...
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0answers
87 views

How can secure email be used while avoiding government attention?

Presumably all unencrypted email is available to federal agencies including IP addresses, header information, and email content (eg, through SMTP with or without SSL and TLS -- thunderbird has an ...
3
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1answer
138 views

Are there any passwords managers that use a second hidden encryption drive to hide passwords?

I've heard that encyption program, Truecrypt can create a hidden encrypted drive within an encrypted drive; and even if an attacker accesses the first encrypted drive he/she cannot prove the hidden ...
0
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1answer
85 views

Is this data encryption process secure?

I have created the following encryption process which I will be using to store CD keys inside my database. Before I use it, however, I need to make sure that this is as secure as possible. From what ...
3
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1answer
118 views

Can applying second cipher (including home brew) reduce security

I have asked a question regarding the benefits (if any) of the following scheme: AES(HomeBrew(plaintext)). There are many good answers for that, but many people say that it's theoretically possible ...
10
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8answers
1k views

Double encryption with home brew algorithm

Everyone says that home brew encryption is not a good idea because one day the algorithm will be known to attacker which sounds reasonable. So that seems it's main problem, on the other hand known ...
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1answer
57 views

Are encryption algorithms designed to hinder parallelization?

Are things like large memory requirements and constantly mutable state typically added to encryption alogrithms to hinder the ability of attackers to try multiple candidate keys simultaneously? Also, ...
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1answer
73 views

Basic XOR cipher for longer messages

How much effective strength is the following adding to a basic 512 bit XOR cipher? Private Key = Key0 consists of 512 randomly generated bits. This key is never used to encrypt or decrypt anything. ...
4
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1answer
153 views

Sending Encrypted Messages with Hybrid RSA, AES and HMAC SHA-256

Is this a Secure strategy for sending a large Encrypted Message using Hybrid RSA 2048, AES 256 and authenticated with HMAC SHA-256: Given the Alice already has Bob's RSA Public Key, Alice: ...
9
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2answers
260 views

How secure is “Firefox Hello”?

The new "Firefox Hello" feature promises easy and safe video conversation. It is not nescessary to create an account, you simply share a link with your partner to start the conversation. The ...
2
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1answer
132 views

if a public key cannot decrypt the cipher text, then how can a private key?

I understand the "public" part of public key cryptography. Not the "private" part. For example, let's say our public key is %7 (modulo 7). And the message to be encrypted is 22. And we know that 22 ...
3
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1answer
53 views

In postgres LDAP authentication, are passwords encrypted?

I am wondering if postgres LDAP login is secure? Would passwords be transmitted in clear text potentially if this is not set up properly?
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2answers
59 views

What are the advantages in using LUKS + hardware encryption on SSD?

I can't see what the advantages might be, but I think this would slow data transfer down while providing no extra protection. Am I right or am I overlooking something?
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1answer
89 views

How to encrypt columns in a database and be able to easily change encryption key

I have several fields in a database table I would like to encrypt, but I would like to do it in a way that would allow me to easily change the encryption key every n months for security reasons. My ...
2
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1answer
67 views

multiple encryption layers and removing them in any order?

I was just thinking (through browsing the site) How possible is it to encrypt data, then encrypt it a 2nd time and then after encrypting it with a 2nd layer, remove the first layer leaving the second ...
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1answer
44 views

On Mac OSX using FileVault 2, are all user's files unencrypted if the current user has rights to login from cold boot up?

I am taking my Macbook into an Authorized Service Provider to run diagnostics on battery performance and my data is encrypted using FileVault 2. I am assuming the technician(s) will want the ability ...
3
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1answer
107 views

Decryption using GRUB and TPM

I'm trying to plan security routine for my new Linux install and few questions came up during searching for solution which meet my needs. Is it possible to use private key from TPM in GRUB to ...
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2answers
70 views

Clarification about IV in PBKDF2 to generate encryption key

I've realized that the following implementation isn't truly safe: $pb = pbkdf2('sha256', $_POST['pass'], "enc_salt", 100, 100); $d = openssl_decrypt ($data['container'],'aes-192-cbc', $pb, true, ...
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2answers
119 views

What stopping someone from offering distributed and encrypted email? Just like Bitcoins

Basically Email service that is ran over a network, so it's not owned by any one entity. Everyone can use it and send email to someone else. All messages travel through a web of interconnected ...
2
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1answer
53 views

What is the output length of CBC with zero input?

Given this formula for CBC encryption from 6.2 The Cipher Block Chaining Mode what is the output length of CBC if plaintext P is of length 0?
9
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2answers
187 views

What real life scenarios require separate end user certificates for Signing and Identity?

Based on this question, I'm interested in any rational argument that would support the idea of maintaining separate signing and authentication certificates. Conventional logic & wisdom says there ...
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2answers
155 views

Protecting my encryption algorithm if the attacker knows the key

Today our programming professor challenged us to make a text encryption program: we will hand him a program that only encrypts (not the source code), plus a ciphertext generated by it. We win if he ...
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2answers
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Standard (or solution) for securing files in a point-to-point integration

I'm looking for a relatively light weight way to secure both integrity and confidentiality for files being uploaded in a point-to-point integration. The use case is uploading batch files for ...
2
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2answers
63 views

DEK, KEK and Master keying - simple explentation

This article is intended to be a simplified explanation sans drill-down for people wanting to understand the concept terms. What is DEK, KEK and MEK/Master key ?
2
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1answer
53 views

Is a Fernet token's timestamp a security risk?

A Fernet token has the following format: Version ‖ Timestamp ‖ IV ‖ Ciphertext ‖ HMAC As the above shows, the timestamp is not part of the ciphertext, so anyone can read the time the token was ...
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0answers
65 views

A Solution for Block/File Encryption that is Corruption Resilient? [closed]

Question: What encryption features/(configuration options) are implemented that mitigate issues with device/block corruption? For example, if the external hard-drive gets dropped, the damaged ...
3
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3answers
136 views

Should traffic between two hosts in the same data center be encrypted?

We have two hosts, theoretically in the same data center. The two machines are hosted at Online.net. We're having a bit of a debate: should the traffic between the two hosts be encrypted. The traffic ...
2
votes
1answer
48 views

Difference in size avaialbe in encrypted volume [closed]

I was making a volume with trucrypt and I set the size to be 12MB. I tried copying 10 files totalling 7.13MB (on Disk) but got an error saying I did not have enough space. Why is this? Is it because ...
3
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2answers
76 views

Is it possible to construct a specific AES collision?

Suppose I have a plaintext message P, and I encrypt it using key K to get ciphertext C. It's trivial to find a different plaintext message P' and a key K' so that the encryption results in C: just ...
5
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2answers
114 views

Encrypting Data Without Sacrificing Query Performance

We're building a cloud web app backed by a multi-tenant db. To maximize security we plan to encrypt each customer's data with a separate key. The problem is querying. Say they're in the report ...
8
votes
2answers
401 views

*NIX shadow file password format

I'm trying to get shell access to a router and have managed to retrieve its /etc/shadow file: root:$1$$N76hdwGfg11g0KdKbtyh21:0:0:root:/root:/bin/bash I've tried to use john to crack it but ...
5
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2answers
65 views

Understanding digitial certifications

q1) Does that mean that every time information is exchanged, both the original data + digital certification is sent? Meaning data + signature for each and every exchange. q2) Can any kind soul here ...
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2answers
131 views

How to make sure my data is secure even if someone gains physical access?

I've been reading up on how to secure my data if someone has gained physical access to the machine, e.g. stolen it. And that seems like a very hard thing to do, as indicated by a number of posts. It ...
1
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1answer
72 views

Create Public Key using OpenSSL instead of PuTTYgen for PKCS#8

I'm trying to create a public key pair for ssh-rsa authentication. If I'm using puttygen.exe, the "OpenSSH authorized_keys file" string looks like this: "ssh-rsa AAAAB3 ... 6yIK9Nbw== ...
1
vote
1answer
116 views

Decrypt a file by knowing the original content [duplicate]

We had some ransomware get into our system a couple of weeks ago, and it has encrypted a large amount of our files. I am wondering, is it possible to figure out an encryption key if I know the ...
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0answers
51 views

Are there any “best practice” encryption tools for these classifications? [closed]

I appreciate there are different requirements when it comes to protecting data – however to try and get a better feel of the security landscape.... ...when considering the CIA triad: ...
2
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1answer
57 views

Hushmails “Secure Forms” & HIPAA

I just picked up a job for integrating Hushmail's Secure Web Forms into a medical website. The forms will submit patient's (PHI) data to Hushmail's servers, encrypt the data, and then send it to their ...
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1answer
114 views

Is it possible for someone to read Gmail messages with a man in the middle? [duplicate]

Assuming these hypotheses: 1) Your account isn't hacked (hacker has not entered your account directly) 2) Gmail encrypts via SSL end-to-end 3) The hacker is not Gmail or Google 4) There is no ...