Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [file-encryption]

The process of encrypting individual files on a storage medium and permitting access to the encrypted data only after proper authentication is provided.

The process of encrypting individual files on a storage medium and permitting access to the encrypted data only after proper authentication is provided.

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Any good file format alternative to PGP for encrypting data at rest?

I'd like to create an encrypted file that: Can be decrypted on a variety of platforms (mainly Windows, OS X, and Linux) with knowledge of the key. Can be decrypted with existing tools (perhaps writing a shell script piping together common tools).…
Jeff Moser
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How to securely store data? / How to securely encrypt a file?

How do I safely encrypt a file? or formulated differentely: How do I safely store the data of my application in a file? Note: Using established tools isn't an option for this. The tasks need to be done at program level (using libraries and such).
SEJPM
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ccrypt and its security

I would like to know how secure is ccrypt to encrypt files (like images, videos and other non-plain text data) using single password of 20+ chars length. It uses Rijndael with 256-bit block size and 256-bit key size. Is there any better alternative…
PSSGCSim
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Can I use my own implementation of a widely used, supposedly secure cryptographic algorithm for securing data at rest?

I know you shouldn't roll your own crypto and generally its not a good idea to implement (and then deploy) any extensively tested and recommended algorithms by yourself either. I have already seen this question, and as far as I understand, the main…
nobody
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Structure of encrypted office files

I try to find out the structure of encrypted office files (I'd like to implement something like a carving tool for finding certain encrypted file types). I try to understand the Office Document Cryptography Structure Specification but this seems to…
tom
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Is ecryptfs safe after unmounting but before turning off the computer

I've read that one of the vulnerabilites of ecryptfs is leaks to swap memory, and that the solution is to encrypt swap. But even if swap is encrypted, it's still open until I reboot. I've also read in this answer, from the designer of the ecryptfs…
snowape
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Given an encrypted file, what are possible ways to find its encryption algorithm?

Given an encrypted file, what are possible ways to find its encryption algorithm? Heuristic ways are okay as well.
Azad
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Question about decryption

I have a question about decryption. Let's say I have a bunch of files that are encrypted. Someone gains access to those files, and finds out that he already has one of them, unencrypted. My question is, can he use that file to make a comparison with…
kat
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Loss of data due to encryption

Could any kind of encryption method (AES, etc.) lead to data loss like in lossy compression? I'm interested if data (lossy compressed, lossless compressed, uncompressed) that is encrypted and decrypted will always come back in the same state as…
user20190
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What is the fuss about 'dot blockchain' and music metadata?

and how does it work? http://wmot.org/post/music-money-and-metadata-promise-blockchain#stream/0 claims that this is an answer to the metadata woes of the music/recorded media industry. I don't see how it can possibly prevent rewriting the file.
Sherwood Botsford
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Encrypt a file for multiple persons with different keys?

I thought a problem and want to ask if there's a more elegant solution. The scenario: A company with a fileserver, which hosts encrypted documents. The files need to be accessible by about a dozen employees. Now the condition is, that each employee…
SEJPM
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File Size Shrinks After Encryption

I am a Bitcoin enthusiast, but I have never been formally trained in the study of computer science and cryptography. Recently, I tried a new way to encrypt my private key: I wrote it down on a paper, and used my camera to take a photo of that paper…
Valac
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can pdfcrack software crack a 128 bit encrypted pdf file

One day ago,i downloaded a pdf that requires password then i search a software to decrypt the password that's s/w called pdfcrack Then i install pdfcrack and run a cmd in terminal pdfcrack -f encrypted.pdf then it shows a some of sentences like that…
ksivasuriyaprakash
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