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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4answers
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Will editing a Word file from a mounted Truecrypt volume leave any trace behind on the host computer?

I've heard that even if you have a Word document encrpyted (just using the built in Word encryption tools) and are editing it, it can still leave behind remnants of a file on the local computer in ...
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0answers
125 views

Is volume level encryption enough to satisfy compliance requirements?

We are implement a cloud application and using nosql technology. We know there are quite a few compliance requirements out there require doing data encryption at rest. However, we would like to know ...
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3answers
1k views

Data encryption risk with bad sectors?

A few decades ago, I've known hard disks and floppy disks which developed bad sectors or crashed. So now when I want to use an external hard disk for backups for a startup company, the first thing ...
2
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2answers
3k views

Does Wanna Cry encrypt files on network drives?

I've dealt with ransomware threats in the past, such as LOCKY that not only encrypt data it considers user documents found on the local machine, but also on any network drive to which the user has ...
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1answer
248 views

(Why) does an encrypted MS Office 2010 Spreadsheet (need to) have the password hash “written down”?

To my naive mind, it seems like the encryption of a document with AES should go like this: HumanPassword ---|hash|--> key ---|AES|--> Ciphertext plaintext|--^ And the ...
1
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1answer
94 views

Encrypted file system in a hosted linux system

I'm considering to use an encrypted file system (dm-crypt or gocryptfs) in a linux system hosted by Linode. Can the administrators of Linode access the mounted (i.e., decrypted) contents? I'm not sure ...
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2answers
1k views

Is it possible to recreate a file using only its hash [duplicate]

To my knowledge, a file can have only one hash and a hash corresponds to only that file(keeping aside the 2 file one hash bug). Using that knowledge is it possible to make an algorithm to recreate a ...
1
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1answer
156 views

Hardening password-based file encryption with a synchronous stream cipher plus high-memory hashing algorithm?

So this is probably a stupid question, but I'm trying to understand why the following isn't done for at-rest files encrypted via password: generate an AES-256 key/salt/iv take the plaintext message (...
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1answer
255 views

which places are used to store the the encryption key? [duplicate]

So i have an encryption key which i will use to encrypt data or sign data with it. But in order make it possible to ensure the data integrity, i have to keep the key secret. So i thought of spliting ...
2
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0answers
82 views

Windows EFS Files Spontaneously Unavailable

We are trying to secure a folder with over 1 million very small text files using Windows EFS on Windows Server 2008 R2. We already have an infrastructure in place for backing up keys and data. We ...
6
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5answers
1k views

Is encrypting home sufficient?

I currently have a fully encrypted Windows System, and I'm looking at switching to Ubuntu. Is encrypting my home directory (with ecryptfs) sufficient? On windows this would be problematic due to ...
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0answers
89 views

Is there a good way to use to find out how this was encrypted [duplicate]

Ok, so this is a very basic cryptography question. I have captured a message from an Android app to a server. I believe this app may be stealing information from the phone it is on so I'm running it ...
2
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2answers
570 views

Encrypted NAS where only clients know the (decryption) key

Is there an implementation of a file-sharing network protocol where the server has no idea what data is being stored, but can serve the encrypted files to clients that will decrypt them on-the-fly (if ...
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6answers
7k views

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 ...
1
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6answers
2k views

Downloading a file from a server with a secret: in text or binary?

Suppose, a user can click a button on a website and downloads a file with a secret. Via ajax. Is it more secure if a server generates that file and sends it as 1) zip, tar or the like -- a binary ...
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2answers
179 views

How to create a format that is very difficult to reverse engineer? [closed]

I am learning about file formats. I have an application that will do analytics and will have some personal information. I need to make it such that only some people are able to access data and even ...
1
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1answer
235 views

Secure file storage in cloud as backup

At start I'll admit I'm a total newbie when it goes for stuff I want to achieve, but I'm willing to learn, so sorry in advance for writing total nonsense. Stuff I want to achieve: I want to store my ...
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0answers
87 views

Encrypted file to Remote Storage

Suppose I wanted to send some files to a remote storage device and (reasonably) guarantee their security and I am wondering whether something like the following method would be suitable: Encrypt a ...
2
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1answer
342 views

Best way to secure a cross-platform mobile app for HIPAA compliance

I'm developing a cross-platform, offline first mHealth application using Ionic 3 and Cordova which may need to be HIPAA compliant in the near future. It uses PouchDB as a client-side DB, HTTPS, at-...
1
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1answer
79 views

File encryption at rest, password considerations

I have at most 10,000 files that I want to store encrypted with one password. The current idea is: Have 1 master file containing (expensive) parameters for scrypt. For encryption/decryption hash a ...
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0answers
212 views

Encrypting File System Data at Rest on Windows Web Application

We have a web application (running in Apache Tomcat on a Windows Server 2008 machine) that stores most of its data in the file system. We are investigating ways to implement encryption for this data ...
2
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2answers
173 views

What is the point of encrypting my files (on a server); if I can decrypt them why can't a hacker do that too?

I help maintain a webserver that users use. They store data on our server. Most of the data is not sensitive, but some of it is highly sensitive. So, it seems like we want to encrypt it so that if ...
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1answer
129 views

User login credentials used for file encryption

A system I'm implementing requires a user to create a single user, with a single login password. I want to have a single password for the system, and not require multiple different password entries ...
15
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5answers
12k views

VeraCrypt/TruCrypt - I can't understand why you'd want to create a “hidden” volume…?

I can't think of a reason as to why you'd want to create a hidden volume in VeraCrypt. It says because "you may be asked to hand the information," but why would I need to hand it over? Nobody has any ...
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0answers
55 views

Secure upload/download design with malicious storage server

Assume we have a malicious storage server (a user-agnostic key-value store, supporting server.put(key, value) and server.get(key)) that we want to use for per-user based secure file storage. The two ...
3
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1answer
170 views

How is encryption different for Windows yet they are identical?

I right clicked on C:\Users\USERNAME and did advanced -> enable encryption. On one laptop it turned green. The other it shows an icon on the files with a lock. What is the difference between these? ...
9
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3answers
439 views

How can I allow access to encrypted data if only 2 out of 3 users provide a secret?

I want to encrypt data, but make sure that no single user can decrypt the data. Further, it is important not to require ALL users to be present to decrypt. This will allow for some flexibility and ...
9
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5answers
331 views

Could ransomware be stalled while encrypting?

I have been reading about ransomware, and I was wondering if it could be defended against by having certain "trap" files on a drive. Sometimes I look through Code Golf and am thoroughly impressed by ...
6
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1answer
1k views

What is the impact of RSA key's size on CPU load?

I use ssh connection encrypted and compressed. If I use small RSA keys or very big RSA keys, what is impact on CPU load for compression, for decompression and on bandwidth (encrypted file size) ?
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2answers
1k views

How to encrypt a file with code? [closed]

How can I encrypt a file using my own programming code? I am a beginner, I want to learn encryption.
2
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1answer
401 views

What's the point of encrypting a session key with a master for file backups?

I was reading the Arq backup data format specification. In short (if I've understood right) it is: Generate password protected master key Generate random session key Encrypt plain text with session ...
8
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2answers
2k views

Ccrypt versus 7zip encryption

I'm on Debian and I have a folder, with thousands of files inside it, that has a size of about 14GB. From this folder I have created two encrypted archives: one is a password protected .7z archive, ...
2
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1answer
313 views

Is it safe to encrypt multiple files with the same strong passphrase?

I use GPG to symmetrically encrypt multiple files, and it would be more convenient if they all had the same strong passphrase. It's possible that someone could gain access to several of these files. ...
2
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1answer
190 views

Securing connection credentials on a web server

I'm in process of creating a tiny blog platform and I've encountered a pretty controversial topic of storing connection string to a DB securely on a host. Here is a reference question: How to encrypt ...
2
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1answer
391 views

How can I compare GPG encrypted files in order to upload only the ones that have changed? [duplicate]

This question follows this one, in regards to encrypting files individually in order to upload them to a cloud service. --- Scenario: I have my folder full of unencrypted files Via script I make a ...
3
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1answer
2k views

Will new data written to disk while BitLocker is encrypting the disk be encrypted?

When you enable BitLocker, there is a period of time where BitLocker is slowly encrypting the contents of the drive in the background. During this time, is it guaranteed that new data written to the ...
13
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1answer
999 views

Secure backup encryption with OpenSSL

I know, the general advice is "keep your hands off crypto stuff". And the standard way to encrypt backup data securely would be using GnuPG. However, for a rather academic exercise, I would like to ...
105
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11answers
18k views

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 ...
3
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2answers
593 views

Brute force algorithm to break symmetric key. How to find the program when current key is the correct one?

In a brute force program, sequential keys are tested against the public key in order to find the correspondent private key. My question is, how is the test done with each key that let you conclude ...
0
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1answer
544 views

Is the MSWord password protection vulnerable?

When encrypting MSWord documents within the Word 2016 app (most recent file format .docx) what encryption algorithm is used? Have any vulnerabilities been found thus far? Has it been audited? Edit: ...
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3answers
3k views

Is it possible to combine RSA and AES? [closed]

I'm working on a new project that encrypts folders on my personal computer.No sending of files are involved(networking). It is only for protection and security. Is it possible to combine RSA and AES ...
0
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1answer
128 views

Getting my first HDD encryption [closed]

So my friend told me about this thing called disk encryption, how you can protect your data if your computer were ever to become compromised.. Now I go to a school where there are alot of bad people, ...
2
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3answers
619 views

Isn't file encryption good enough?

As the title asks, and in conjunction, I'm wondering why full-disk encryption is "better" to some folk. This is not taking into consideration of theft, but rather, something or someone infecting my ...
11
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1answer
496 views

Is it possible to decrypt half of a TrueCrypt file container if the other half of the data is missing?

Let's say we have half of a TrueCrypt file container (e.g. download was interrupted). If we know the password, is it possible to open it and get half of the data? The original container has 10 files, ...
11
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4answers
10k views

Are MySQL's database files encrypted?

I'm trying to securely store user credentials in a MySQL database which is hosted on a different server than the application (the communication between the two is secure). I have initially assumed ...
-1
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1answer
167 views

Check to see if public key provided is PGP/openPGP compatible

I'm still new to encryption and differences between an RSA public keys and PGP/openPGP compatible public keys. First of all, is there a difference between an RSA public key and a PGP/openPGP ...
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2answers
9k views

Determine Security Of A PDF File [closed]

How do I find the exact encryption on a PDF file? I can't seem to get a direct answer on the net. For example how do I tell if a document is PDF 1.1 - 1.3 (Acrobat 2 - 4), PDF 1.4 - 1.6 (Acrobat 5 - 8)...
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2answers
137 views

Inherited a project with a backdoor to manage; code was promptly stolen by a known entity. What's next?

I have a doozy for you - almost posted this in the project management stack. I was asked to oversee a development of a project. At some point the previous manager thought it was prudent to create a ...
0
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1answer
141 views

How secure is an archive file if the password is cryptographically random?

I looked for an answer for this question over here, yet all I could find were about cracking the password. So let's say I'm using PHP to generate a cryptographically secure random password: echo "...
1
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1answer
60 views

Securing folder being accessed by batch file

I will state up-front that I know fairly little about encryption and could be asking a silly question, or asking a good question in a silly way. Thank you in advance for your patience. I have a ...