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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How do I securely encrypt and store database encryption keys? [duplicate]

I have a database with encrypted information, and want to encrypt each entry with a different key. Then I want to store the encrypted keys in another database. I know I have to encrypt the keys before ...
14
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2answers
17k views

Is it possible to use S/MIME in the web client of Gmail?

I could not find any options in the web interface of Gmail. All I could find was a Firefox plugin to use S/MIME with Gmail, but it seems to be outdated.
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1answer
329 views

How does the Signal Protocol, used by WhatAapp, work?

I want to understand the process of the Signal Protocol. I have google it, but I am unable to find any good article or tutorial. I want to understand the basic definition and functionality of the ...
2
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2answers
238 views

How to tell if an email is encrypted, or just corrupted?

Ran a recovery program (Kroll Ontrack) on a Windows 7 PC and recovered many, many emails. Almost all of them open in my Windows 10 mail client (and Thunderbird), except for a handful from this March. ...
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2answers
164 views

store passwords as one-way-hash, or just use it as an AES key?

I want to store some data so the only one who'll be able to access it is the user itself. Here is my idea: when user registers, his password will be hashed in SHA256 (so it'll fit as an AES key), and ...
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2answers
112 views

Are the websites I visit using Windows Remote Desktop connection secure from my ISP?

Are the websites I visit using Windows Remote Desktop connection secure from my ISP? I am ok if my ISP knows the IP address of the remote desktop I am connecting with but will they also be able to '...
15
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4answers
81k 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 ...
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2answers
70 views

Asymmetric Encryption for Multiple Recipients?

Let's assume an arbitrary group of people who hold a key pair and who make their public key online accessible. Let X, A, B and C be arbitrary people from that group. Now X wants to encrypt a message ...
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2answers
26 views

Security fails in private key and xor

I've implemented a very short program to encrypt a file, and send it on a remote server. First, I build a key based on a pass-phrase and a subset of prime numbers (the length of the key is defined by ...
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1answer
86 views

Handling user login using asymmetric cryptography

Is it possible to implement a login protocol with asymmetric cryptography instead of the hashed password method? For example, while creating an account, the client generates a private/public key pair ...
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2answers
97 views

What's the best place to hide long lived encryption keys

I am considering encryption options for a new Sybase project (internal facing only, sitting in our intranet) for a client that has a security policy that requires all sensitive data to use DB ...
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0answers
60 views

Would encrypting a signed JWT prove viable to secure claims payload?

I am working on a server-client web application, and as an authentication scheme, I am issuing base64 encoded json web tokens. Consider the following token... eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9....
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1answer
64 views

OpenSSL brute-force attacking and file size

I use OpenSSL with aes-256-cbc to encrypt a 30 GB tar file containing a recent backup of my hard drive. Now suppose somebody wants to run a brute-force attack on this file, trying out all possible ...
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1answer
49 views

Why is CBC-MAC insecure for variable length input?

Can anyone explain why CBC-MAC is not secure for variable length message? I read many books, but there are still some confusion. Like the highlighted parts in following pictures Slide 32: Slide 33:...
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2answers
217 views

encryption using two keys

The use case is analogous to accessing a safe box in a bank. There is a per-user key, unique for each user, either generated by the system or hashed from the user's password. And there is a system-...
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2answers
106 views

Is encrypting a CRC with the plaintext ok?

We're using encrypt-then-mac for authenticated encryption, and recently added a CRC32 to the plaintext. Are there any security problems with using a non-authenticated hash mechanism (for example, ...
137
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5answers
134k views

Is Telegram secure?

There is a new WhatsApp-killer application called Telegram. They said that it's open source and that it has a more secure encryption. But they store all the messages in their servers and WhatsApp ...
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1answer
97 views

Is it possible to to encrypt multiple messages with multiple keys and get only one cipher?

I want to have cipher which when people decrypt it with their own key, get different meaningful messages. Is this possible at all?
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1answer
153 views

How secure is FaceTime by Apple

Apple says their messages and FaceTime calls are end-to-end encrypted and nobody can access them. As I'm unfamiliar with cryptology, I've found security white paper from Apple, where says: ...
3
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1answer
123 views

Offering a privacy scenario with PHP mcrypt library

first of all, sorry if my question is not clear, because English is not my first language. Anyway, let-me explain the concept I'm struggling to solve as the best solution. I have some guys, and they ...
2
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2answers
83 views

Is there a difference between getting encryption key versus encrypted data from server in terms of security

Suppose we have web and application servers and trying to encrypt credit card information for our financial web application. Communication between web and app servers are secured through SSL/TLS. Lets ...
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1answer
64 views

Making an encrypted SMS app (Android) [closed]

From my limited googling I've noticed that a lot of the mainstream encrypted messaging apps all are either (or a combination of!) closed-source, run through an uncontrolled third-party server, use a ...
0
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0answers
69 views

Is the QUIC protocol secure?

QUIC is a new protocol for video streaming, that can establish a secure connection in one round. It is used in Google's new Duo app for example. How does it work and is it secure (comparison with TCP ...
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0answers
80 views

Security of the shared secret key for a smart meter (Linky) [closed]

Reading the specs of a new electricity smart meter (called Linky in France), I was surprised about the chosen encryption method (128 bits symmetric key AES), based on a single secret key (called CCC ...
3
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1answer
128 views

DES Decryption followed by Encryption, will it produce the original text?

This is regarding DES. My question is, if a plain text is first decrypted (with the decryption algorithm) using Key K1 and then encrypted using same K1, would the result still be the original plain ...
5
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1answer
138 views

How to share an encryption key between different PHP applications?

I'm working with the php-encryption library to provide integration between two different applications. On one side, I have a corporative application that holds all data from users. This application ...
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1answer
57 views

Crypto++ RSA - Encrypt and sign with the same key pair

I have a program A which needs to send messages to several instances of program B (B1, B2, etc...). The messages must be encrypted, and also signed. Which means only Bn instances can decode, and they ...
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1answer
89 views

Windows security & data protection

I work for a hotel. The hotel stores a MySQL database online. This database only contains a Reference ID, number of nights and so on, but no private data. No names, no personal information on guests. ...
5
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1answer
134 views

How to protect TimeMachine backups from Ransomware?

According to Heise (German) Time Machine backups can be encrypted by Ransomware. Sorry I didn't find an English source, please use Google translate. KeRanger had an inactive module ...
3
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1answer
3k views

SIP Provider stores credentials, is it required for some SIP phones?

My SIP provider stores my SIP call time password as AES encrypted in stead of hashed. I understand that SIP authentication has the capability to NOT store the password, and in stead store a pre-...
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0answers
61 views

End-to-end encryption without user-keys interaction

Is it possible to have true end-to-end encryption even if the user is not involved in generating, selecting, transporting, or storing of the keys?
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3answers
972 views

How do poor-quality initialization vectors affect the security of CBC mode?

(If the consensus is that this question belongs on crypto, rather than here, please feel free to [tell me to] migrate it.) From what I have read (looking specifically at AES in Cipher Block Chaining ...
10
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3answers
1k views

Is it safe to sync private keys between iOS devices using iCloud?

My iOS app has to handle storing private keys for the user. Normally I would just use Keychain Services for this as I would a password, but it would be great if I could sync the keys between the user'...
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45 views

VPN chain in one machine without VM natively

Is it any way to make VPN chain in one machine (MAC or WIN) without VM natively (L2TP/IPsec)? I need this for obtain an extra layer of security. For example - if one VPN turns off I still have ...
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0answers
38 views

Preventing a key from being found by analysis

Lets say Alice wants to send an encrypted message to Bob. They both know a secret key. Alice uses the key to encrypt the message and Bob uses the key to decrypt the message. Now, if the handshake ...
16
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3answers
11k views

Is email encryption, as claimed by ProtonMail, possible?

Is it possible to create a Web service that encrypts all messages, such that only the writer, and the person to whom the mail is sent, can read it? In other words, is the theory behind ProtonMail ...
1
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1answer
109 views

Wi-Fi Protected Setup PIN method EAP Messages

Let's look at this example: router (access point) has 8-digit PIN (printed on label) and laptop wants to connect to network using WPS PIN. So user give router's PIN into laptop and laptop sends PIN to ...
6
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0answers
51 views

Why would I use at-rest encryption over a DB's key-based encryption?

Goal I want to store encrypted data in a database. Constraints Application-level encryption (encrypting before sending to the DB) is not a reasonable option for my use case. The DB providers I'm ...
20
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1answer
16k views

What changed between TLS and DTLS

What did the DTLS (TLS over UDP) authors have to change so that it could run without TCP? Bonus points: Do any of the protocol difference affect the way it should be used, both in terms of interface ...
6
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4answers
6k views

What does Windows's built-in encryption do, if I can seemingly always read my encrypted files?

I'm playing around with certificates and encryption on a Windows system, but either it isn't working or I don't know how it should works. When I encrypt a file its name changes to green. But then, I ...
15
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6answers
24k views

What does “key with length of x bits” mean?

I'd like to know what it means to say "the cryptosystem C uses keys with a length of x bits". I do not understand what the bits length means... doesn't it depend on the encoding? The same word encodes ...
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1answer
151 views

How can this encryption algorithm be improved?

I am currently developing an application to store my passwords safely. It will be a proof-of-concept at first, but I am planning to upgrade it later. Anyway, here is how the passwords are accessed: ...
2
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2answers
106 views

What information can my ISP see using squid proxy?

My ISP provides a transparent proxy to use and I can see that they are using the squid proxy for caching this. What I am wondering is what data can they see and what can they see further if they can ...
20
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2answers
3k views

Why was DES with 112 bit keys (IBM) reduced to 56?

On the French wikipedia page about DES it says that the original DES algorithm from IBM used 112 bit keys. Why did they reduce this to 56 bits? Edit: ok NSA convinced IBM but today it seems like a ...
2
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1answer
53 views

Is EFS FINRA and SEC Acceptable

I'm trying to search in their manual but there is nothing explicit being mentioned as to what type and how encryption should be done. Can I assume that if I use EFS on the entire USER directory that ...
7
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1answer
228 views

Encrypting individual files on OS X

I am about to go paperless, and I want to protect the documents that I scan. The use case is that I'll be scanning paper documents, encrypting each file, and storing them locally and on various backup ...
1
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1answer
98 views

Should the RTP feed from a surveillance camera be protected?

I see a lot of camera system and they're either using RSTP over RTP or just RTP. Most of the times they are on straight HTTP for the login, some will be on HTTPS, but unless forced (which I have seen)...
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1answer
230 views

Is this algorithm really end to end encrypted and secure?

I'm creating an anonymous chat where one of the premises is that the conversations are end to end encrypted. I'm using firebase so all the comunication between the clients and the server is SSL ...
15
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2answers
1k views

What's the difference between a hashed and an encrypted password?

Alright, so I know this may sound dumb, but I'm having a hard time understanding what an encryption would be since it's different from a hash. I've read up on it, but I'm still not quite sure. So, I ...
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1answer
266 views

How to use nmap through proxychains?

Iam running nmap through proxychains using this comand proxychains nmap -v scanme.namp.org This produced an error showing like this root@kali:~# proxychains nmap -v scanme.nmap.org ProxyChains-3....