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.
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Is it dangerous to encrypt lots of small files with the same key?
I want to encrypt 1000s of old files on old hard drives before uploading them to the cloud. I'm planning to use AES-GCM with only one or a few keys. (I'm using Apple's CryptoKit library which provides ...
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Encryption of big files in Java with AES/GCM
I have to encrypt big files. Say their size ranges from 500mb to several of gigabytes.
I would like to use AES/GCM/NoPadding as provided by Java 1.8 since that gives me automatic authentication and ...
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What is safer: ZipCrypto or AES-256?
Like in title: which one of these encryption methods (ZipCrypto, AES-256) is more secure and why? I am asking about it because I'd like to know which should be preferred when compressing files with ...
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Information leakage from the ecryptfs filesystem
I'm wondering what information might be leaked from the ecryptfs filesystem. This is what Ubuntu uses if you check the box for "encrypted home directory" when using the desktop installer, so is ...
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Is it safe to use file's hash as IV?
I'm encrypting some files using AES in CBC mode.
I'm also using file's digest (SHA-1) to check that data is decrypted correctly (so I need to store it with file).
Is it safe to use this digest as ...
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Twofish vs. Serpent vs. AES (or a combo)
I've seen some posts and info online, but they are from 2009, 2010, 2011 or 2012, which is 3-6 years ago, which is a very long time. So I'm looking for an up-to-date answer about which of these is the ...
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Is it possible to get an RSA encryption key by comparing the unencrypted and encrypted file?
Exactly what the title says. If I have a RSA encrypted file, and the exact same file but decrypted, can I tell the key that was used from that information?
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A specific way for deniable encryption
I read the summary of deniable encryption on wikipedia:
https://en.wikipedia.org/wiki/Deniable_encryption
Then I read a question, by doom123 on security.SE:
https:/...
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AES-CTR security if S-boxes substituion is omitted?
I understand why s-boxes are needed in general especially when ECB mode is used(because of using the same key for encryption of other blocks)but I wonder if it's ...
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Sharing an encrypted file between a group of people
Is there any way to share an encrypted file with a group?
In the other words, can I encrypt a file with a public key so that each person in a group decrypt it with his/her private key?
Is there any ...
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How to encrypt many files with AES-GCM, without running the key derivation function each time?
Linked question: AES encrypting multiple files
With a password, I have 100k files to encrypt. (Maybe 100k files today; or maybe 50k today, 10k tomorrow, and 40k ...
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What is a safe maximum message size limit when encrypting files to disk with AES-GCM before the need to re-generate the key or NONCE
The general limits from the NIST recommendation are as follows:
Maximum Encrypted Plaintext Size ≤ 239 - 256 bits;
Maximum Processed Additional Authenticated Data ≤ 264 - 1 bits;
This stack ...
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Best way to generate a IV for AES-CBC when encrypting files?
The situation is that I want to use symmetric encryption to store some info in files. I'm going to use AES-CBC algorithm. The user is going to remember the password (meaning it will not be stored ...
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Hash decrypts key, key decrypts cipher... why?
I noticed recently that a couple of pieces of encryption software (TrueCrypt being one of them) don't directly use a hash of the password as the key for the block cipher. Instead, they generate a ...
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When is it safe to not use authenticated encryption?
I have read the post Why should I use Authenticated Encryption instead of just encryption? When is it safe to not use authenticated encryption?
I assumed hard drive volume encryption or per file ...
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Reusing AES-CTR Keys and IVs for File Encryption
I’m implementing some file encryption module with random-access capability and AES-CTR seems the right way to go.
I understand that reusing Keys and IVs can expose the file to ‘Stream Cipher Attacks’ ...
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Proper way of encrypting large files with AES-256-GCM
I would like to encrypt and decrypt files with AES-256-GCM. I need a solution that works with Java, PHP and JavaScript. In practice, users can upload, download files via web browser and/or desktop app ...
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How to perform file encryption using 128-bit AES
I am confused. How can I encrypt a file using 128-bit Advanced Encryption Standard?
Do I need only to encrypt the file name and it's content or is there something that I need to do to encrypt it? Is ...
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How to securely store data? / How to securely encrypt a file? [closed]
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 ...
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Encrypt multiple chunks of data with an AEAD
Assuming that I want to encrypt a 1 GB file with e.g. AES in GCM mode or ChaCha20Poly1305.
[I'm specifically referring to the cryptography module for Python: https://cryptography.io/en/latest/hazmat/...
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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 ...
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Non-malleable file encryption using AES XTS 256?
I'm looking to do file encryption of a bunch of individual files, some small, some quite large. The files will be write-once/read-many, so I could use CBC, however, since the read-access needs to ...
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File encryption with AES CTR mode
I understand that encrypting files in CTR mode is not perfectly safe, because it potentially leaves the files open for cryptanalysis, if the attacker has access to previous versions of the same files. ...
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Capacity of Advanced Encryption Standard in terms of File Encryption
what is the capacity of AES in terms of File Encryption?
is it really good to encrypt a large files in AES? ex. I am encrypting a 8GB of File... is it still good to used AES?
is it still good to used ...
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What are best practices for long term storage (~20 years) of encrypted / sensitive files?
I have some very sensitive family files that I want to store in the cloud on multiple providers for maximal reliability and redundancy. It's essentially a large archive of all our family photos, ...
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Does Encryption add difficulties to File Recovery?
Seems Yes. People always tell us, it is very hard (or almost impossible) to recover an encrypted hard disk.
But after a second thought. I think this is not true.
Given that we know the KEY, and the ...
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Decryption a chunk of file with AES
We are having a requirement to store large files (~1GB) encrypted and decrypt them when reading. We are looking to use AES-CTR or AES-GCM mode to encrypt the data. There are scenarios where we want to ...
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how much is secure to encrypt a password using itself (as encryption key) for storing it on an insecure media?
I want to store a password securely on a storage (suppose in a usual unencrypted file).
I use this password as AES key to encrypt itself (using AES-ECB) & then store it on the media (the password ...
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Decrypted RSA 64 bit encryption using modulus and private exponent. Got gobbledygook [Verify] [closed]
As part of an experiment, I was given a .enc RSA (encrypted) file that was most likely generated using openssl. I had the public key, I factored it, obtained the private exponent, and decrypted the ....
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Encryption using ASCII instead of bits and bytes (clarification in the body)
I am new to cryptography and I am trying to understand something. I searched it on the internet, though the question is probably a simple one, couldn't find an answer. So, please don't judge me by ...
