Questions tagged [encryption]
Encryption is the process of transforming information using an algorithm to make it unreadable to anyone except those possessing special knowledge.
2,893
questions
132
votes
7
answers
419k
views
SSH: The authenticity of host <host> can't be established
What does this message mean? Is this a potential problem? Is the channel not secure?
Or is this simply a default message that is always displayed when connecting to a new server?
I am used to ...
129
votes
25
answers
26k
views
How to find and remove "spicy" media files from my PC [closed]
I have an embarrassing problem: during my younger and wilder days, I used to download a certain type of movie clips and pictures. The combination of youthful foolishness and a couple of beers ...
116
votes
6
answers
88k
views
How can I use encryption with Gmail?
I'm currently reading Cory Doctorow's novel Little Brother which includes a part about encrypted messaging, and even wrapping messages first in my private key and then your public key.
I'd like to ...
109
votes
10
answers
400k
views
How to access a BitLocker-encrypted drive in Linux?
I have a laptop running Windows 7 Ultimate. I have encrypted my drives using BitLocker. Now I have also installed Lubuntu along with Windows. But my encrypted drives are not visible in Linux. How ...
90
votes
7
answers
42k
views
Compress and then encrypt, or vice-versa?
I am writing a VPN system which encrypts (AES256) its traffic across the net (Why write my own when there are 1,000,001 others already out there? Well, mine is a special one for a specific task that ...
87
votes
14
answers
175k
views
Which TrueCrypt Algorithm is the safest?
If performance is of no concern, which TrueCrypt algorithm is the safest to use?
AES
Serpent
Triple DES
Twofish
AES-Twofish
AES-Twofish-Serpent
Serpent-AES
Serpent-Twofish-AES
Twofish-Serpent
82
votes
5
answers
71k
views
How to use ssh-rsa public key to encrypt a text?
So, the scenario is: Given I'm Bob, I want to encrypt some message for Alice. The only public key I have is her ssh-rsa id_rsa.pub like this:
ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAyb+...
72
votes
4
answers
45k
views
What are the correct permissions for the .gnupg enclosing folder? gpg: WARNING: unsafe enclosing directory permissions on configuration file
I don't want to just chmod and run until I get the right answer, nor do I want to run GnuPG as root. The easy fix would be to just set it so that only my user can read it, but I don't think that's the ...
70
votes
1
answer
53k
views
How do I symmetrically encrypt a file using gpg?
I'm trying to symmetrically encrypt a file using gpg.
$ gpg --encrypt --symmetric $MYFILE
I enter and re-enter a passphrase, then gpg tells me
You did not specify a user ID. (you may use "-r")
...
70
votes
8
answers
32k
views
Is TrueCrypt truly safe?
I have been using TrueCrypt for a long time now. However, someone pointed me to a link that described the problems with the license.
IANAL and so it really didn't make much sense to me; however, I ...
67
votes
3
answers
89k
views
Simple built-in way to encrypt and decrypt a file on a Mac via command-line?
Are there any built in command-line tools that I can encrypt and decrypt a text file (and provide it some sort of password).
63
votes
6
answers
48k
views
What is better for GPG keys - RSA or DSA?
ssh-keygen defaults to creating RSA keys, but gpg --gen-key prefers DSA/ElGamal.
Which one - RSA or DSA - is better for GPG?
61
votes
4
answers
45k
views
Does full-disk encryption on SSD drive reduce its lifetime?
I would assume that a full-disk encryption deployment would introduce additional writes each time the computer is booted up and shut down. Given that solid state disks are considered to have a lower ...
59
votes
5
answers
33k
views
Setting up an encrypted git-repository
Situation
Hi, I would like to save data with git, encrypted (on some platform like bitbucket or github). Therefore the question:
Question
I am looking for different hassle-free ways on:
How to set ...
57
votes
8
answers
63k
views
How to do Rsync-like encrypted backup?
I want to save a backup of my data on a remote server, but never want the backup server to see the data unencrypted.
Editing a single file and backing up should not result in everything being ...
57
votes
1
answer
7k
views
Short, easy to understand explanation of GPG/PGP for nontechnical people?
Does anyone have a link to a good, but short (1-2 paragraphs) explanation of the benefits of using GPG/PGP signing and encryption for Email focused at non-technical readers? That is, why would someone ...
53
votes
3
answers
38k
views
How secure are password-protected zip files?
In modern zip utilities like 7zip, you can specify a password when creating a .ZIP file. But, how secure is this? What encryption algorithm(s) are used to secure password-protected zip files?
49
votes
8
answers
12k
views
How to mitigate any privacy-related risks associated with taking your laptop for repair? [duplicate]
Either my fan or my battery on my refurbished laptop is malfunctioning and it frequently overheats and shuts itself down. I wasn't able to determine the culprit and thought it best to show my laptop ...
49
votes
2
answers
7k
views
Does changing the encryption password imply rewriting all the data?
Let's say I have 1 TB of data on a partition encrypted with BitLocker, TrueCrypt or VeraCrypt.
Does changing the encryption password imply rewriting all the data (i.e., will it take hours/days)?
49
votes
2
answers
36k
views
Best encryption and signing algorithm for GnuPG: RSA/RSA or DSA/Elgamal? [closed]
I have found this relatively old question about whether RSA or DSA is the preferred algorithm for signing and encrypting with GnuPG.
When using gpg --gen-key, the two relevant choices are either "RSA ...
49
votes
11
answers
51k
views
Speed of TrueCrypt whole disk encryption
I'm getting a new development laptop soon, and I'm thinking of using TrueCrypt to encrypt the whole disk.
What kind of performance drop can I expect? 10%? 30%? More? Also, assuming the workload has ...
45
votes
1
answer
52k
views
How do I fix "WARNING: message was not integrity protected" when using GPG symmetrical encryption?
I've encrypted a file using symmetric encryption like this:
gpg --symmetric myfile
which results in a file myfile.gpg.
Alright. Now let's decrypt the file again:
gpg -o myfile --decrypt myfile.gpg
...
44
votes
3
answers
150k
views
How to set password on already existing winrar archive and encrypt it also?
Not when creating new archive, but on existing archive. I would also like to know how to do that in other archiver.
43
votes
8
answers
72k
views
How to list encrypted files in Windows 7?
I somehow encrypted some files without meaning to, and because of it I can't backup my user folder to Mozy. Is there a way to remove the encryption from all the files or at least find out which one ...
43
votes
2
answers
155k
views
is there a way to stop mac osx disk encryption in progress?
I chose a 1T external drive for time machine and checked the "encrypt backups" option. I thought it will only encrypt the backups, but as it seems it is now encrypting the whole drive which has quite ...
43
votes
3
answers
122k
views
How to specify private key when decrypting a file using GnuPG?
I am trying to decrypt a file with GnuPG, but when using the command below:
gpg --decrypt filename.gpg
I get the following message:
gpg: encrypted with RSA key, ID 3662FD5E
gpg: decryption failed: ...
41
votes
18
answers
14k
views
Can I encrypt data in a way that it can be read normally but can't be copied or edited? [closed]
I want to share my 500 GB hard drive with a friend but I want to encrypt it in a way that all data can be read normally but cannot be copied or edited in any way.
Is that possible?
41
votes
17
answers
50k
views
How can clients easily and securely send me passwords? [closed]
I often need to get passwords from clients for FTP, SSH, MySQL, Authorize.net, etc.
What's an easy way for them to send me passwords securely? Maybe even without them needing a login/password?
...
41
votes
1
answer
9k
views
What does BitLocker actually encrypt and when?
I need full disk encryption for business laptop computers running a current version of Windows 10 Pro. The computers have an NVMe SSD drive from Samsung and an Intel Core i5-8000 CPU.
From some web ...
39
votes
2
answers
47k
views
Mount encrypted HFS in ubuntu
I try to mount an encrypted HFS+ partition in Ubuntu.
An older post described quite good how to do it, but lacks the information how to use encrypted partitions.
What I found so far is:
# install ...
38
votes
9
answers
60k
views
How to encrypt a file or directory in Linux?
What's the most popular command to do such things as encrypting a file or directory in terminal in Linux?
37
votes
5
answers
34k
views
How does SSH encryption work?
I've read about generating 2 keys (private and public) on client host and copying the public key to the server host.
As I understand it, (correct me if i'm wrong): The server encrypts data with the ...
36
votes
3
answers
8k
views
Can Google Employees See My Passwords Saved in Google Chrome?
I understand that we are really tempted to save our passwords in Google Chrome. The likely benefit is two fold,
You don't need to (memorize and) input those long and cryptic passwords.
These are ...
36
votes
9
answers
2k
views
Password Cracking Windows Accounts
At work we have laptops with encrypted harddrives. Most developers here (on occasion I have been guilty of it too) leave their laptops in hibernate mode when they take them home at night. Obviously, ...
34
votes
6
answers
9k
views
What can I do if someone tampers with my SSH public key?
I understand private keys being compromised is a huge risk; however, what about public keys. What if they are tampered with?
If someone were to access my public key associated with the private key I ...
34
votes
5
answers
71k
views
How does Google Chrome store passwords?
Are they encrypted in disk? How? Are they safe, for example, in the event of someone booting from a Live CD and mounting the hard disk?
How is the encryption key generated? Is it different in ...
33
votes
5
answers
108k
views
How can I access volumes encrypted with LUKS/dm-crypt from Windows?
The answer to this question used to be FreeOTFE (https://en.wikipedia.org/wiki/FreeOTFE); sadly, the project has not been updated for three years and its website (http://www.freeotfe.org) is no longer ...
31
votes
10
answers
47k
views
BitLocker asking for protection code after Ubuntu installation
I have just installed Ubuntu side-by-side to a Windows 10 partition shipped on a new laptop.
Meaning, the laptop shipped with Windows 10, and I installed Ubuntu alongside the Windows partition using ...
31
votes
4
answers
29k
views
Encrypted WiFi with no password?
Is there any standard that allows a WiFi connection to be encrypted, but not require a password?
i know that (old, weak) WEP, and newer WPA/WPA2 require a password (i.e. shared secret). Meanwhile my ...
30
votes
10
answers
20k
views
Determining if a hard disk has been removed and data copied from it?
Is there a method or a tool that can detect if someone has separated my hard disk from my computer, copied data from it, and returned it back?
I want to be sure that no one has done this without my ...
30
votes
4
answers
67k
views
How can I encrypt a string in the shell?
Can I encrypt a message (string) using a public key at the command prompt? Also, how can I decrypt the result afterwards?
30
votes
4
answers
15k
views
Is it safe to store (encrypted) passwords on GitHub?
I am using pass to handle all my passwords. They are encrypted using GPG with a 4096 bits key, using the SHA256 algorithm. I am using a different password for every login in my password store.
One of ...
29
votes
1
answer
15k
views
How does S/MIME differ from PGP/GPG, for the purpose of signing and/or encrypting email?
In addition to the titular question, are the two technologies compatible? If so, under what circumstances?
What are the relative benefits of the two technologies?
29
votes
4
answers
21k
views
How resilient are VeraCrypt and LUKS encrypted volumes against data corruption?
The question has been partly answered, but that's still not what I'm exactly looking for. See for Update 1 down bere
I'm planning to encrypt some filesystems with VeraCrypt and LUKS, but my fears are ...
28
votes
10
answers
3k
views
Encrypted HDD 100% safe?
I guess am a bit of a paranoid ha... anyway i encrypted my HDD with truecrypt using all printable ASCII characters and the password is 64 characters long. It is quite random, certainly no dictionary ...
26
votes
4
answers
80k
views
What does the encryption setting of uTorrent do?
I'm having trouble finding precise information about the encryption setting of uTorrent. From what I understand, it's used to hide the torrent traffic from ISPs so that they cannot make the difference ...
26
votes
1
answer
15k
views
How to delete a subkey on Linux in GnuPG?
I would like to delete an OpenPGP subkey of mine on Linux (L)Ubuntu 16.04 in GnuPG. It's a kind of "blank" useless key (see below key 33333333). I have not uploaded it to key servers, so I think it's ...
26
votes
4
answers
26k
views
How to mount an encrypted ext3 filesystem under OS X?
I know how to mount an ext3 filesystem in OS X with MacFUSE and fuse-ext2. But how can I mount an encrypted ext3 volume?
I have Mac OS X 10.6 "Snow Leopard" running.
25
votes
5
answers
113k
views
Windows 10 Password Error with Samba Share
I am trying to connect to a samba share with Windows 10 Pro (Version 1511, Build 10586.589) using the command net use L: \\myserver\myshare /u:myuser mypassword. I get the error:
System error 86 - ...
25
votes
2
answers
21k
views
Is zip's encryption really bad?
The standard advice for many years regarding compression and encryption has been that the encryption strength of zip is bad.
Is this really the case in this day and age?
I read this article about ...