Questions tagged [encryption]

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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11
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1answer
6k views

How to choose a stream cipher

Are there high-speed ciphers designed for things like internet streams without sacrificing security? There are so many options that operate in stream mode. How would one choose a cipher?
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1answer
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Should I include a random padding in every HTTPS request and response?

According to the following paper, it is possible to decrypt HTTPS traffic by inspecting AJAX calls and using the size parameter as a cryptographic oracle. Should I be sending a variable length ...
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1answer
8k views

Cellular encryption algorithms currently in use globally

I have been doing research on the available encryption algorithms used by commercial mobile providers worldwide, and would like to know if the following list is complete: Algorithms for voice ...
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4answers
3k views

What Partial Homomorphic Encryption implementations exist and how do I leverage them?

It appears that only Partial Homomorphic Encryption(P.H.E.) is practical for modern day (2011) use. However I'm having difficulty locating libraries (FOSS or otherwise) that enable me to leverage ...
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2answers
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sniffing/recording GSM 3G signals

Is it possible to sniff or record and process GSM 3G signals (from some reciever) given that there is no other signals interrupting etc (the most comfortable conditions) Update (with some supporting ...
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1answer
7k views

How secure is full-disk encryption technology on LineageOS, or Android phones in general?

We're attempting to assess the information security on our mobile devices, and information seems rather varied on the question of encryption. Is the encryption technology employed by Android-based ...
27
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6answers
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Why did TLS 1.3 drop AES-CBC?

I was watching this video about TLS 1.3: "Deploying TLS 1.3: the great, the good and the bad (33c3)" and was somewhat surprised to see that in their effort to provide "fewer, better choices" they ...
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3answers
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Is it safe to write the salt AND/OR the IV at the beggining of an encrypted file?

I want to encrypt a file with AES in CBC mode (maybe another mode is better for file encryption...I don't know, but suggestions are welcome!). What I usually do is that I first write a few random ...
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3answers
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Why triple DES used in EDE mode?

Why is triple DES is calculated in encrypt decrypt encrypt mode? Why a decrypt in the middle? And isn't decrypt = encrypt since DES in a symmetric cipher?
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8answers
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Is Steganography a safe method to store secret data?

I want to put some parts of my secret data into specific file with Steganography method. Is this method as safe as other encryption methods like RSA or SHA?
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3answers
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When do I use IPsec tunnel mode or transport mode?

I basically understand how tunnel mode and transport mode works, but I don't know when I should use one instead of another. Among the two parties who want to communicate, if one computer B doesn't ...
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3answers
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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 ...
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1answer
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XTS vs AES-CBC with ESSIV for file-based filesystem encryption

In a blog post I recently read called "You Don't Want XTS," the author explains some of the pitfalls of using XTS to encrypt filesystems. Specifically, he recommends against ever sharing encrypted ...
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2answers
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How secure is GnuPG conventional encryption (with defaults)?

How secure is the encryption of files when using GPG this way? gpg -c personal.zip It will not use any keys or other lines. And how good is it compared to TrueCrypt? Note that I will upload ...
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5answers
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Storing private asymmetric key in application binary?

I would like to give a daemon-style process (i.e. no user interaction) access to a shared secret key so that it can access a shared, encrypted data file. User applications accessing the same encrypted ...
12
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5answers
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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 ...
11
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2answers
2k views

How could a system be zero-knowledge?

I'm actually interested about zero-knowledge storage system. Those system where the storage provider claims he can't have any access to the data stored. As far I know, the data are encrypted using a ...
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1answer
2k views

Is it possible to assign different UIDs to subkeys for the purpose of having multiple identities?

Many people advocate generating new primary keys for each identity they wish to have. For example, creating one primary key and associated subkeys for workplace use, and a completely different ...
19
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1answer
7k views

Ransomware encryption keys

Where does ransomware such as the recent wannacry variant store the key it uses to encrypt the files on the victim's disk? Is this hard coded in the program itself? Or does it call into a server to ...
18
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2answers
6k views

What is the purpose of associated authenticated data in AEAD?

Authenticated encryption (AE) and authenticated encryption with associated data (AEAD, variant of AE) is a form of encryption which simultaneously provides confidentiality, integrity, and ...
15
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4answers
12k views

What's the standard way to encrypt a file with a public key in Java?

I'm writing a client app in Java that sends encrypted data back to the server. All clients have my RSA public key. Is there a standard way to encrypt a given file with it to send it back to the server?...
13
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1answer
2k views

Handling “forgot password” functionality with encrypted data without security questions

As a sort of follow-up to this question on handling password-reset functionality when dealing with encrypted user data, is there any good method for resetting a user's password in an encrypted web ...
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5answers
12k views

How can I decrypt data with Java, without hard-coding the key?

I hope this is not a chicken-egg problem or reinventing the wheel but here goes. I have a Java application that needs to access a password protected file (actually during the application startup). The ...
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9answers
4k views

Is there any asymmetrically encrypted file system?

Is there a file system providing a directory where everybody can write, but only the directory owner can read the files? In theory it could be done by encrypting using the public key while writing, ...
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3answers
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Encrypt WiFi connection per connected user

One of the questions that comes on quite often is about WiFi encryption. Now imagine that you have multiple users connecting to one AP. With a simple WPA2 protection setup they can still sniff each ...
10
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3answers
9k views

How can i find what hashing algorithm was used?

One of my clients has asked me to modify the login page that their board members use to access their materials. The problem here is that the person previously responsible for this has left no ...
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3answers
21k views

Is the 3DES algorithm secure?

Can we use the 3DES algorithm for exchanging confidential information? I am using it in my project. Security code reviewer has raised a bug saying that it is not secure but I see that it is mentioned ...
9
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1answer
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Reversible, recoverable user data encryption scheme

From this earlier question, I have a general need to obfuscate a set of third-party credentials stored in a user account, which are then used in an internal Winforms software client. The scheme from ...
8
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1answer
25k views

How can I tell if a PPTP tunnel is secure?

PPTP has been demonstrated to be broken in many ways, and most installations are insecure. But it is also theoretically not broken if configured correctly. As an end-user, is there a simple way for ...
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2answers
3k views

Explain BCrypt like I'm 5

I know this is a little bit broad, but I'd like to understand the function of this algorithm by explaining like I'm 5. And I'd like to know the difference between BCrypt and blowfish, is it because ...
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2answers
9k views

What's the limit on the size of the data that public-key cryptos can handle?

Someone mentioned here that asymmetric encryption might not be appropriate for bulk data and gave an example of RSA with 100 bytes. Of course, I understand that it was a rough example. But it made me ...
5
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2answers
14k views

How can I recover encrypted files after system reinstallation

I had a file which contains images and videos, I was using the windows 7 ultimate and I had encrypted the file. Now I have copied that file to my hard disk and format that operating system and again. ...
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2answers
2k views

What data is not encrypted in iOS 8+ when “locked”

Scenario: iPhone 5+ with iOS 8+ with system encryption enabled. The phone is on and locked. (the user has authenticated (unlocked phone) at least once since power-up, and then relocked). What data/...
4
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1answer
2k views

Is there a best practice for storing passwords in a two way encryption?

I have a .NET system with users logging in normally and standard hashing and/or 3rd party login (google, fb etc). I have a 3rd party plugin that requires username/login for each user in addition to ...
4
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3answers
20k views

Chrome showing cryptography as 'obsolete' [duplicate]

Similar to this question, Chrome is showing the connection cryptography as obsolete. Opera, IE and Firefox seem perfectly fine with the connection. My guess would be the message authentication is ...
3
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2answers
524 views

Encrypted retrievable password

I have a password conundrum. I need to store an encrypted password in a DB table but in such a manner that would allow me to retrieve the password as plain text afterwards. Please note that this is a ...
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1answer
2k views

Web App encrypting data on client with login password?

I'm writing a web app for Personal Information Management that runs in the Cloud. For that I'm considering client-side encryption using AES256 with window.crypto and SJCL as fall-back for older ...
20
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5answers
4k 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 ...
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4answers
17k views

Can Cryptolocker (Or Other Ransomware) Encrypt Files That Are Already Encrypted?

If you have already encrypted files, are they still vulnerable to being encrypted a second time by a program like Cryptolocker, or would this protect them?
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2answers
14k views

WPA2 Enterprise AES encryption key size?

I have recently set up a RADIUS server with EAP for my wireless router, however, I have some questions about the key size and how WPA2 enterprise (AES) works in general. I have read that in ...
11
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5answers
9k views

How To Prove That Client Side Javascript Is Secure?

Imagine that you have a web application that encrypts the user's data, such as a note or spreadsheet, on both the server and client. The normal process for a user using this web application is ...
11
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2answers
4k views

Data Encryption and Key Management in C#

Which route to take, what are the pros and cons, which is more secure.. Generate AES key, encrypt the data with it and then encrypt the AES key with RSA, save the encrypted data and encrypted AES key ...
10
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2answers
32k views

Why would you need a salt for AES-CBS when IV is already randomly generated and stored with the encrypted data?

I was looking at this code and came across these comments which says encrypting without a salt is insecure. Why would it be insecure when you are already using a random IV for each value? I think the ...
9
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2answers
4k views

Does GnuPG use symmetric + public key encryption for large files?

Recently, I have a need to encrypt few large files. I have the option to use the OpenSSL command line utility, however I prefer to use GnuPG. How does GnuPG works under the hood with the --encrypt ...
9
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2answers
8k views

Are Telegram secret chats secure assuming MTProto isn't?

For those who don't know: Telegram is a partially open source Whatsapp alternative (Server is closed source) which offers secret chats and normal chats. Secret chats are encrypted with Diffie-Hellman ...
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3answers
3k views

What are the disadvantages of using public key cryptography when encrypting files? [duplicate]

I am wanting to encrypt a file with my public key, my friend told me that this is not a good idea but did not explain why. Can someone explain please.
8
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1answer
3k views

Encrypting sensitive data in software and storing/decrypting it on a server

I have searched IT Security and Google for something similar to this, but wasn't able to find anything remotely related to what I'm doing. I'm developing software which has 2 parts - a C# program run ...
7
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2answers
3k views

Considering that SRP is better than SSH and Basic Auth, how can it be implemented in a website?

SRP is short for Secure Remote Password protocol, and provides a better way for passwords to be sent over the internet. I've read the information at it's Stanford University home page, the Wiki ...
7
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1answer
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What is “NAND mirroring”, the alleged technique that the FBI will use to crack the San Bernardino shooter's iPhone?

According to Ars Technica, Jonathan Zdziarski, a leading independent Apple iOS security researcher and forensics expert, has a theory about the FBI's newly discovered potential route into the ...
7
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2answers
2k views

Is AES 128 encryption weak for very small payload size?

If I have a payload of e.g. 8 bits and I want to encrypt it using AES 128, I will need to add some random padding to make the plaintext 128 bits long. Does this padding affect the security of AES?

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