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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7
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0answers
196 views

Linux, TRESOR and XTS

I want to switch from using LUKS for full disk encryption to TRESOR. TRESOR tries to prevent cold boot attacks by storing the encryption key in the CPU's registers. It uses the kernel's crypto API for ...
29
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5answers
6k views

How do I verify that WhatsApp is using end-to-end encryption?

Slightly old news: Whatsapp Just Switched on End-to-End Encryption for Hundreds of Millions of Users Is there any test that I can perform to verify that WhatsApp is indeed using end-to-end encryption ...
1
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0answers
25 views

Is a direct SIP video call (encrypted) between two computers more secure than going through a registrar service?

I learned recently about ZRTP-encrypted video calls using an SIP client, such as Jitsi or Linphone or Blink. I was able to make a direct encrypted video call between two clients on the same local ...
47
votes
5answers
12k views

Why should one not use the same asymmetric key for encryption as they do for signing?

In an answer to a question about RSA and PGP, PulpSpy noted this: It is possible to generate an RSA key pair using GPG (for both encryption and signing -- you should not use the same key for ...
3
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0answers
272 views

What are the vulnerabilities of this homemade encryption algorithm? [migrated]

I decided to program a relatively trivial encryption algorithm in my downtime. This algorithm takes a seed from a user (supports floating point seeds), and then adds 1 to the seed for every iteration ...
1
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1answer
48 views

Secure point to point remote access to NAS drive

This question is very similar but also distinctly different (How do I ensure data encryption on Samba transmission on *NIX systems?) I'm looking to set up remote access to a NAS unit locally sharing ...
1
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1answer
72 views

Any way to revoke old key pair?

There is a many-year-old 1024 DSA key in the public keyservers under my name. There is a 2048 ELG-E subkey for it. I didn't create these keys, they were created for me by a former employer without my ...
0
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1answer
57 views

Decrypting encrypted traffic with hacking an app [duplicate]

I am thinking how does telegram ensure that messages are secret. I understand they use the public key to encrypt and private key to decrypt. Why is it not possible for an attacker to download the ...
2
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2answers
119 views

Save application autostart login token on computer

I need to login desktop application while autostart on server (like skype does). What is the best practice to save authentication token (password)? Should I use something like RSA encryption (which ...
2
votes
1answer
45 views

Authenticity of PDF document printed from Word

My MS Word Add-In generates PDF preview of DOCX file on client PC and uploads both files to server. I cannot generate PDF on server. Is there any way to make sure that the PDF is the printed version ...
27
votes
3answers
7k views

symmetric encryption session keys in SSL/TLS

This question concerns the session send and receive keys used in SSL/TLS protocol. my understanding is that this key uses symmetric encryption (DES, AES, BlowFish, etc.) I'm wondering, if ...
0
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2answers
61 views

Is End to End security possible without physical contact?

I noticed that a lot of messaging start to provide "End2End" security, but I wonder how this can be possible without a key exchange between the the two clients. To my understanding to provide real ...
3
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3answers
139 views

Acceptably secure solution for users to log in with a short unique code only (no username)

I am creating a website whereby users are given an account by invitation only, and are sent a unique code by post. Users can then log in (at least the first time) by entering the code only. The goal ...
6
votes
1answer
6k views

Are there any known vulnerabilities in PPTP VPNs when configured properly?

PPTP is the only VPN protocol supported by some devices (for example, the Asus RT-AC66U WiFi router). If PPTP is configured to only use the most secure options, does its use present any security ...
0
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0answers
22 views

Securing decentralised cloud scaling

Approach Require a certain percentage (quorum) of nodes to agree in order for my decentralised multicloud to grow. Benefits Reduced likelihood of growing too quickly (e.g.: 2 new nodes created ...
1
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0answers
36 views

Hiding symmetric key inside encrypted data

My server generates an AES encrypted file which when downloaded acts as an input for an application. So, should I hardcode the symmetric key inside the application or should I randomly generate the ...
3
votes
1answer
95 views

Asymmetric / end to end encryption for web messaging app

Background I'm trying to design a secure and sustainable web app for messaging. The purpose is to learn how to create secure web application. The application is suppose to be written in Javascript ...
16
votes
9answers
3k views

Hide the fact of e-mail communication

Bob has a mistress. Her name is Alice. Bob`s wife Eve knows Bob is unfaithful, but she does not know who the mistress is. Alice does not know Bob is married. Bob needs to communicate with Alice over ...
23
votes
7answers
37k views

How secure is a Windows password protected zip file?

I need to send some sensitive information to a client. I thought I would email a password protected zip file I created using Windows XP and then call them with the password. Presuming I pick a good ...
3
votes
0answers
98 views

Generate secure one-time codes containing information

I need to create a system that allows a user to enter codes to charge an allowance. Embedded in this code should be the amount to charge the allowance. The user would pay for a code which would then ...
1
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0answers
41 views

OpenID Connect: Why use authorization code flow?

I have a question about implementing OpenID Connect I was hoping I could get some help on. I understand the different flows and get that the authorization code flow is good because it allow client ...
4
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0answers
34 views

Is there any reason to use AesManaged over DPAPI in this scenario?

I have a situation where my web application is going to be deployed on multiple web servers, and I'll be wanting to store some securely encrypted data on the DB servers (each web server has a DB ...
0
votes
2answers
152 views

Is this the most secure encryption/hashing system? [closed]

I've been doing some research regarding password security and after reading several topics and the Kerckhoff's principle. I came up with what I believe is a really secure system regarding online ...
14
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3answers
4k views

Smartphone / GSM Sniffer

This question would be in the category of SmartPhone Sniffers. So we have sniffers that can show the packets that are being sent across a wired or wireless (802.11) network. I am just performing a ...
11
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1answer
1k views

Why can't I use the same key for encryption and MAC?

I wrote a simple file encryption program as an example of how to do encryption correctly, but after reading a questions about encryption + MAC, I think I made a mistake by using the same key for both. ...
0
votes
1answer
80 views

Safely encrypting data received through HTTPS

I am receiving sensitive data over an HTTPS connection and need to store this on disk, encrypted so no one can tamper with it, but for reading later on. Each user in the system has a password. The ...
2
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2answers
134 views

Which hard disk encryptions schemes are tied to the original hardware?

When using a laptop, an encrypted HD/SSD can be an important security measure. However, laptops are prone to accidents (fluid spills, dropping on the floor, etc) that may mandate some or all of the ...
2
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2answers
128 views

Converting ECC Private key to PKCS#1 format

Is there any way to convert an ECC private key to RSA PKCS#1 format? I have tried converting it to PKCS#8 first using OpenSSL: openssl pkcs8 -topk8 -nocrypt -in EC_key.pem -out pkcs8_key.pem This ...
3
votes
1answer
449 views

Why does GnuPG shrink my file after elgamal encryption?

I would like to run GnuPG elgamal encryption for at least a few minutes. The only way I can think of is to create a large file to be encrypted. So I created my file like this: dd if=/dev/zero ...
1
vote
1answer
80 views

What is the safest way to encrypt a password that can be decrypted at a later time?

In a web app I'm building, I need to use Apple's AutoIngestion tool for iTunes Connect. In this tool it seems the only way to use it is to send a password in plain text. What would be the best ...
29
votes
4answers
20k views

How does PGP differ from S/MIME?

Is S/MIME an abstracted system for general MIME type encryption, whereas PGP is more for email? Why would I want to choose one over the other, or can I use both at the same time?
3
votes
1answer
158 views

Has the POODLE SSL vulnerability ever actually been used?

Is there any evidence that the the POODLE SSL or TLS has actually been proven to be a risk for file transfer like SecureFTP etc...? ...or is it just a theoretical exposure?
0
votes
1answer
53 views

Security at application layer

Originally asked on http://crypto.stackexchange.com/questions/24430/security-at-application-layer but was suggested to ask here instead. I saw lots of questions asking about encryption over http, ...
2
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2answers
1k views

What are the security implications of the POLi Internet Payments technique?

POLi Payments is an Australian based online payment provider which has begun trading in New Zealand. They are supported as a payment option on some large eCommerce websites in New Zealand, including ...
14
votes
4answers
13k views

Is RedPhone a secure and secret way to communicate?

RedPhone provides end-to-end encryption for your calls, securing your conversations so that nobody can listen in. But really, how is the probability that a voice conversation is wiretapped still? ...
2
votes
2answers
56 views

Does changing the default number of iterations in KeePass (or other encryption applications) increase security?

Inspired by this question about the difficulty of cracking a KeePass database, I'm wondering if changing the default number of iterations in an encryption application (e.g., KeePass) increases ...
4
votes
3answers
23k views

CryptoWall 3 - how to prevent and how to decrypt?

My father's computer is now infected with CryptoWall 3, according to the link below. http://www.bleepingcomputer.com/virus-removal/cryptowall-ransomware-information#CryptoWall Is there a way to ...
1
vote
1answer
38 views

What's the value of data partition encryption for database files on a postgres database server?

We're in the process of rolling out a postgres based web app, and I'm trying to understand the value of encrypting the entire database. In postgres's case, the only way to do this is store the ...
4
votes
1answer
72 views

Is it possible to prove the content of an encrypted message without disclosing the private key?

Suppose that I sent Bob a message saying, "The meeting is cancelled", and encrypted it with his public key. Could he share the plaintext with other people, without disclosing his private key (and ...
0
votes
1answer
110 views

Why my files that Encrypted with EFS in Windows 8.1 shown in Linux ubuntu?

i Encrypted my files with EFS in windows 8.1 so i logged in ubuntu and without any warning , its shown my files actually not Exactly the file but shown the path of file and the name and i can ...
2
votes
4answers
9k views

Is diskcryptor really secure?

Diskcryptor is an open-source competitor to TrueCrypt for Windows. It has an edge over Truecrypt for system encryption, because it allows for more than one independently encrypted system partition, ...
51
votes
4answers
5k views

What kinds of encryption are _not_ breakable via Quantum Computers?

There's the recent article NSA seeks to build quantum computer that could crack most types of encryption. Now I'm not surprised by the NSA trying anything1, but what slightly baffles me is the word ...
5
votes
1answer
178 views

What are the security differences between SMIME email and PGP email? [closed]

Outside of key distribution, and specific to the technical details relating to encrypted email data (message body), what's the difference between SMIME and PGP? Example comparisons Security ...
13
votes
6answers
4k views

Why encrypt data in memory?

I saw that KeePass not only encrypts its password-database-file, it also can encrypt the passwords it holds in memory. This is just an example. I thinking of a new project dealing with sensitve / ...
2
votes
1answer
49 views

Is there any College, State or Government ID that transmits a offline verifiably encryptable data blob?

I'm looking for any way to digitally verify a user, ideally with a photo and link PII to that user. My use case is that a user will extract and send an encrypted data blob (say from a passport) to my ...
16
votes
4answers
3k views

Is it dangerous to publicly share ciphertext?

Alice wants to share a message with Bob, but Alice and Bob can never be in the same place at the same time. We can assume they both know each others public keys (or agreed on a shared key, if that ...
0
votes
1answer
56 views

WPS and WPA2 connection methods

Do clients use WPS every time when they connect to a WPS-enabled AP? Or maybe they do it just the first time and then they switch to a normal WPA/WPA2 key exchange? If the latter, it's possible for ...
2
votes
2answers
208 views

What is a current best practice example of basic encryption and decryption in PHP?

I have a good working knowledge of basic security best practices (password hashing, preventing sql injection, CSRF, etc.) but am completely at a loss for finding a solution to common-case encryption ...
18
votes
1answer
474 views

How to encrypt in PHP, properly?

How do I encrypt data in PHP, properly, using symmetric-key encryption? I have a message M and a secret S. I'm looking for a solution that uses cryptography properly without making any of the usual ...
0
votes
1answer
109 views

rainbow table for AES 256 CBC knowing IV, cipher text and plain text

I'm in a situation where I know that I have to decrypt a file encrypted using AES 256 CBC and I've the following details: I know the first 16 bytes block in plain text I know the IV (static 128 bit ...