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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11
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1answer
14k views

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 ...
12
votes
5answers
5k 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 ...
10
votes
4answers
7k 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 ...
1
vote
2answers
262 views

Seeking lightweight encryption - shareable between Delphi & C

I want to encrypt a text file in Delphi & decrypt it, line by line, in C on an embedded system which does not have much RAM (so, only one line in RAM at a time). FOSS must be available for both ...
21
votes
6answers
33k views

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 ...
12
votes
6answers
13k views

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 ...
8
votes
3answers
1k views

time to crack file-encryption password - more than just iteration

I have often seen that takes x amount of time to crack a certain length password. But this just seems to be the amount of time it takes to iterate through all the possibilities. What about the time it ...
7
votes
9answers
3k views

How can I share files with other individuals using the cloud in a secure way?

I would like to use a dropbox because it is easy and convenient. But I want to encrypt the files with the public key of the intended recipient, so he will be the only one who can access the data in ...
11
votes
5answers
584 views

Security of using passwords or even passphrases to encrypt files

Is it ever appropriate to use real-world passwords to encrypt files to be sent via unsecure means. By real world, I mean a password that is memorable and memorisable by a mere person? I am implying ...
6
votes
6answers
540 views

Applying file deltas to an encrypted file

I am developing software that will be used for data backup. The server will run on Linux. Security in transportation is not an issue (HTTPS or SSH), but the data must be stored encrypted on the ...
3
votes
2answers
233 views

Security review: is this PHP mcrypt wrapper class safe?

I was looking for an easy to use library for encrypting files in PHP. PHP provides encryption functionality through the mcrypt library. Yet, there is a lot of configuration options and choices, enough ...
7
votes
7answers
2k views

Verify the password of an encrypted file without waiting for complete decryption

I am currently working on an application that encrypts files with AES 256. The problem is that I want the user to see whether the password is wrong before the file is decrypted. For example if you ...
5
votes
2answers
2k views

After How Much Data Encryption (AES-256) we should change key?

Considering AES-256 encryption, what is the maximum amount of data should be encrypted with one key? Does Block cipher modes/IV/counters also governs the limit? If say the maximum amount is 50GB, ...
2
votes
1answer
179 views

AES + CBC to encrypt individual local files, fixed IV?

I am using AES and CBC to encrypt a local files separately. I don't plan to transmit them over any network. What are the risks of using a fixed IV for my encrypting application? The only problem I ...
2
votes
2answers
1k views

How to use 'key material' so that multiple people can access protected files?

I'm not sure if this is the right SE to ask this question, but it seems more I have a database of files that needs to be encrypted such that multiple people with different passwords/logins to this ...
1
vote
2answers
656 views

can I trust Boxcryptor closed source software? Encryption of files for cloud hoster

Boxcryptor https://www.boxcryptor.com is not Open Source. Can I trust this? Is it secure? No government backdoor? Because there is no alternative for OS X and iOS.
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2answers
1k views

Single File Encryption in a Windows Environment

Would it be correct to assume that encrypting a single file in a Windows environment, for example a simple text file containing login credentials for a variety of accounts, is inherently insecure? It ...