IT Security Stack Exchange
IT Security 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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Technology that can survive a "Rubber-Hose attack"

In the documentary film Citizenfour, Edward Snowden says about documents: I'm comfortable in my technical ability to protect [documents]. I mean you could literally shoot me or torture me and I could not disclose the password, even if I wanted…
QBR8ZIKvyJ
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Why would I ever use AES-256-CBC if AES-256-GCM is more secure?

I guess the gist of my question is: Are there cases in which CBC is better than GCM? The reason I'm asking is that from reading this post by Matthew Green, and this question on cryptography stack exchange, and this explanation of an attack on XML…
The Quantum Physicist
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What security scheme is used by PDF password encryption, and why is it so weak?

Many PDFs are distributed as encrypted PDFs to lock out some of their functionality (eg printing, writing, copying). However, PDF cracking software is available online, which usually cracks the PDF passwords in less than 1 second. It doesn't make…
March Ho
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How to recover a lost zip file password?

I have some files I was given by my teacher at University, I could chase him up, but I may as well try getting blood from a stone, his response rate isn't great and I completed my degree a year ago! They're pdf files stored inside password protected…
bluekeys
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Why would an encrypted file be ~35% larger than an unencrypted one?

According to the ownCloud documentation, if you enable encryption, file sizes can be ~35% larger than their unencrypted forms. From my understanding of encryption, the file sizes should be more-or-less identical (perhaps some padded 0 bits at the…
warren
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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 password, how secure is this approach?…
Dave Aaron Smith
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What is the attack scenario against which encrypted files provide protection?

There are a couple of files / tools which provide file-level encryption. I guess PDF and ZIP are probably the most commonly known ones. I wonder what scenario they actually help with or if it just is a bad solution. For example, if I want to be sure…
Martin Thoma
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Does password protecting an archived file actually encrypt it?

For example if I use WinRAR to encrypt a file and put a password on the archive how secure is it? I keep a personal journal and am thinking of doing this, or is there a better way? It's just one huge .docx file.
Celeritas
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How secure is NTFS encryption?

How secure is the data in a encrypted NTFS folder on Windows (XP, 7)? (The encryption option under file|folder -> properties -> advanced -> encrypt.) If the user uses a decent password, can this data be decrypted (easily?) if it, say, resides on a…
Martin
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Is there any reason I shouldn't make a GPG-encrypted file publicly-accessible?

I'm working on a project where we need to keep a few specific files easily accessible, but encrypted. My idea for accomplishing this is to have the files available in the project's public website, encrypted to all of the members' PGP keys. I know…
Chris
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Do spaces in a passphrase really add any more security/entropy?

I often see passphrase suggestions written as a sentence, with spaces. In that format are they more susceptible to a dictionary attack because each word is on it's own as opposed to a large unbroken 20+ character 'blob'?
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Is EncFS secure for encrypting Dropbox?

I've encrypted my Dropbox folder with EncFS according to a few tutorials I found on the web, advocating this approach. But I've found the following critical statement concerning EncFS's security in this security-audit: EncFS is probably safe as…
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Brute Forcing Password to a Truecrypt-encrypted file with Partial Knowledge

A while back, I encrypted a few files with Truecrypt, and stored the password in my head. Now I need to access it again, the password isn't working. I'm sure most of it is right, but I'm off by one or two characters. Is there a program that will…
Robyn
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Strongest file encryption available

I know nothing about cryptography. How does one encrypt a file in the strongest possible way, such that it can be accessed some years later? I prefer that it should be fairly resistant from brute force and other possible ways attacks. I need some…
dave09963
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Does File-Based Encryption offer comparable security to Full-Disk Encryption on Android?

Between version 4.4 and 9, Android supported Full-Disk Encryption (FDE). On Android 7, a new system called File-Based Encryption (FBE) was introduced, and was subsequently made mandatory on Android 10. The primary upside cited in the page for…
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