Questions tagged [gnupg]
GNU Privacy Guard (GnuPG or GPG) is an open source implementation of PGP, a file encryption and signature tool widely used for emails
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Can I resubmit my GPG key to a keyserver?
I submitted my GPG key to the keyserver earlier. Now I got signatures on my key. Can I republish it? gpg --send-keys doesn't seem to alter my key any more, but doesn't spit out any error either.
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1answer
59 views
GPG encryption failed - Unusable public key
I was trying to encrypt a file using a GPG public key.
It's working fine on my test server which is ubuntu 18.04 but when I try to use the same key on my production server (Amazon Linux) it failed ...
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2answers
79 views
Use RSA key to encrypt/decrypt personal document
Suppose I have generated a public/private RSA4096 keypair using GPG. Is it secure to use this keypair to encrypt/decrypt documents solely for personal use, i.e., have an encrypted backup of some very ...
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32 views
How to automatically obtain keys in Evolution for e-mail recipients? (key discovery) [migrated]
I am using the PIM Evolution 3.22.6 for e-mail and contacts. For encrypting e-mails gpg (GnuPG 2.1.18) is used by Evolution.
How can I configure my system such as when I compose an e-mail the PGP ...
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1answer
67 views
How do i validate that a PGP Public Key the user inputs is valid?
we want to encrypt emails that we send to the user with his public key.
this works great, however the user can also type in a broken/invalid public key ("asdf123") and then the encryption won't work ...
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0answers
26 views
What is the best command line option to use to encrypt files using GPG on Mac for personal upload to the cloud? [migrated]
I would like to use gpg on my Mac, which I currently have installed. I saw that a lot of options with the documentation on gpg are for sending and receiving files to someone else, which I am not ...
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0answers
36 views
gpg won't find public key if not in interactive session
How to make imported public key available after logging off?
I have a Powershell process that encrypts the file (recipient was masked):
Start-Process "gpg.exe" -ArgumentList "--batch --yes --always-...
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0answers
20 views
GPG keys generated with diceware entropy?
Considering the absolutely critical role that entropy plays in the generation of keys, I am wondering if there is an easy way to use diceware (true random numbers) to generate an OpenPGP key with ...
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1answer
167 views
Decrypt file using Key and Initialization Vector in Linux
I am Salesforce developer but new to the Security World as well as Linux. We encrypted a file with Key and initialization Vector in Salesforce(only symmetric encryption is possible in Salesforce). No ...
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1answer
49 views
secp256k1 GPG key?
Given that secp256k1 is used to underpin the entire Bitcoin network (worth $174B as of today) -- it appears to offer demonstrably better security than other EC curves as no one has yet taken the ...
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68 views
What should I do next on my GPG key after my computer is seized by authority?
Unfortunately, although my keys are protected by password, I am afraid it is not strong enough. I assume I lost control of all my private keys now. I still have backup of my private keys, what I want ...
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23 views
GnuPG verify signature *after/while* decrypting does not fail when it should
I'm encrypting and signing data with the PHP function gnupg_encryptsign() (docs) which has the strange behaviour of signing first and encrypting afterwards.
I'm aware of this thread saying this is ...
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1answer
66 views
What use does verifying a file with a signature downloaded from the same server have? [duplicate]
Now, I understand how PGP signatures work and why they can be useful to check if a file has been manipulated but this has always bugged me, if I download a file from a site/server, and read:
"...
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70 views
GPG unattended ECC key and subkey generation
I wanna generate a ECC key which primary key is just for cert and has 3 subkeys for auth, sign, encrypt.
I've found 2 methods to generate it. But I wanna unattended key generation via
gpg —-batch —...
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1answer
65 views
Can a deleted PGP secret key be recovered from private-keys-v1.d directory?
Executing gpg -K --with-keygrip returns one key entry. However the private-keys-v1.d directory has two entries. I assume that one of them belongs to a secret key that has been deleted/removed.
Is ...
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0answers
45 views
create gpg public key from subkey
I have a communication partner that is using some script that does not work well with subkeys. Now, my gpg key is a normal key [SC] with three subkeys for E,S and A specifically.
For my communication ...
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1answer
92 views
Difference between OpenPGP symmetric encryption and AES-256?
I would like to understand the difference between:
OpenPGP symmetric encryption
and
AES-256 using Winzip/7-zip?
I mean if you encrypt a file with an OpenPGP program like GnuPG, using AES-256 ...
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63 views
How is private key encrypted after export?
For migration I exported private/public key pair from OSX to whonix. I exported the file to my filesystem and opened the asc file with textedit. The private key to my surprise was in plaintext! I ...
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1answer
50 views
How can one read the time in GPG's Literal Data Packet?
RFC 4880 says that the Literal Data Packet's time stamp is four octets long. Listing packets shows that it is five octets long, at least in GnuPG 2.2.6.
The time stamp comes after the word "created", ...
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1answer
62 views
gpg: Every private key export (of the same key-pair) is different
gpg version: 2.2.16 (as part of Gpg4win 3.1.9).
Is this supposed to happen: Every export of my private key partially differs from every other export as follows: 2 middle chunks of the main block, and ...
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1answer
75 views
Can a new signature be added to an already signed message?
Suppose Bob receives a clear-signed message from Alice. Bob wants to add his own signature to this signed message, because he has verified the message contents and wants his friends (network of trust) ...
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0answers
57 views
How to verify a binary correctly even if my github account is hacked by someone
I have a binary file and saved it on github release page. https://github.com/zono/bolt8/releases
To allow users to verify it, I saved sha256sum and signature(.asc).
However I have a concern that if ...
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1answer
250 views
How can I get rid of the MDC packet in OpenPGP?
I want to get rid of the MDC packet in OpenPGP because I view SHA1 as a catastrophic threat. If one can invert SHA1, then all plaintext in OpenGPG is ... open. If one tries to go back to RFC 2440 ...
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37 views
How can I input a raw session key into GnuPG?
How can I input a raw session key into GnuPG? I presume that I will have to use --sk2-cipher-algo and --sk2-digest-algo at the same time so as to accommodate the length of my chosen session key.
...
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1answer
128 views
Superceding a passphrased key with a token-based key
I've been using a GPG key for awhile (mostly with the pass password manager but also some with mail). Since it's now in use, a few years old, and entering the passphrase is getting tiresome, I ...
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0answers
41 views
--s2k-mode 0 session key from equal-length passphrase
In gpg2, how exactly does --s2k-mode 0 go from the passphrase to the session key in this example:
gpg2 --armor --s2k-mode 0 --s2k-digest SHA256 --s2k-cipher-algo CAMELLIA256 --symmetric [file path]
...
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2answers
145 views
Should I delete lost GPG key from GitHub?
I've been using GPG key for a while to sign commits on GitHub. However, I recently lost it by accident when moving data around. It haven't leaked anywhere and signed commits can be trusted, I just don'...
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0answers
39 views
Import/Register GPG keys from a SmartCard/Yubi
I used my desktop to setup my GPG keys, added them to my Yubikey, and then removed them from my desktop so that when I am prompted for the key it asks me to use my Yubikey --instead of asking for a ...
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1answer
133 views
Is GPG symmetric (decryption) vulnerable?
Suppose a file (say, a text file source.txt) was encrypted into danger.gpg using GPG symmetric encryption on a compromised device. Since the device is compromised, danger.gpg could have been created ...
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1answer
683 views
How do I delete secret subkeys correctly?
I tried to use gpg --delete-secret-keys to delete some revoked subkeys but ended up accidentally deleting my primary key instead.
I was able to reproduce my mistake with the following commands:
$ ...
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1answer
235 views
GnuPG can see a card under root user, but not under normal user
When under an unprivileged user:
$ gpg --card-status
gpg: selecting openpgp failed: No such device
gpg: OpenPGP card not available: No such device
With sudo or under a root user:
$ sudo gpg --card-...
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2answers
255 views
Is it permissible to use GPG without an encryption key?
Will I be disapproved of or get frowned upon a lot if I choose to deploy and use GnuPG without an encryption key? E.g. I generate keys manually and skip the encryption key entirely.
The reason is ...
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0answers
109 views
Import ssh keys into gpg (openpgp) as mutliple authentication subkeys?
I have successfully converted ssh keys to gpg primary keys and then converted them to authentication subkeys using pem2openpgp. Unfortunately there is only one primary key and only one authentication ...
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1answer
216 views
How do I create a detached plain text signature?
If I use gpg --detach-sig file, then I get a small file.sig, but it is not plain text, so this is not useful if you wish to send the signature in a plain text format.
If I use gpg --clearsign file, ...
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0answers
123 views
Is gnupg2 --refresh-keys susceptible to any attacks based on fingerprint collisions?
Alice updates her OpenPGP key yearly. Bob updates his copy using: gpg2 --refresh-keys
Mallory ensures that Bob uses her keyserver, which offers her own key, which
is sharing the 32-bit "short" Key ...
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1answer
148 views
Can I decrypt a .gpg file by using Windows CNG store/ProtectedData?
I'm creating this tool in C# that would take a .gpg file and decrypt it using Windows CNG. I get a .gpg file as my input parameter and it is encrypted with my key using WinPT. Decrypting it works with ...
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1answer
404 views
How do I interpret output that produces gpg listing keys?
Correct me where I'm wrong. There are public and private (or secret) keys. A public and a private key make up a keypair. Some keypairs are bound to the other ones. The former are called subkeys, the ...
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1answer
104 views
Length of a stretched gnupg passphrase that is comparable in strength to an unstretched string of 256 random bits
Assume that we want to encrypt a file with gnupg using AES-256 as the encryption algorithm. (Hence, symmetric encryption.)
In this mode, gnupg requires a passphrase from the user. I understand that ...
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0answers
86 views
How can I trust a GPG key when I download it based on the fingerprint contained in the file I want to verify?
The instructions at https://tutorials.ubuntu.com/tutorial/tutorial-how-to-verify-ubuntu#3 suggest that you can download an ISO for installing an OS, along with the checksums and a signature. You then ...
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2answers
165 views
Is that a good idea? - Firefox/Chrome in-content encryption
I'm currently thinking about writing a Firefox/Chrome and Python/PHP/JS plugin to accomplish the following:
Assuming you are on a non-SSL secured site or you simply don't trust any CA like Let's ...
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1answer
749 views
RSA 4096 vs. ECC Curve 25519
I want to use GPG to encrypt files before storing them as backup in the cloud. I don't care about interoperability or performance/resource consumption during encryption/decription. I only care about ...
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0answers
58 views
Which encryption algorithm for cloud backup?
I want to backup my data to the cloud. Before that, I want to encrypt it using GPG (gpg (GnuPG) 2.2.11 and libgcrypt 1.8.4).
The backup is just for me, so I don't care about interoperability
I only ...
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1answer
172 views
Is there a security difference between GPG signing a file directly or its SHA512SUM file?
I am about to decide what SHA-512 hash sum and / or GPG verification scheme I will choose.
Let me present you with two options:
Signing the 25 GB ~ 23 GiB (one file fit to a Blu-Ray) directly with:
...
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1answer
55 views
Decrypting gpg2-symmetrically-encrypted files using non-gpg2 tools
If I encrypt a file using gpg2 and specifying AES256 as my encryption algorithm, can I decrypt it with tools other than gpg2?
More generally, does the fact that one tool used AES256 for encrypting a ...
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2answers
148 views
Is GPG a kind of digital signature?
So I've been using GPG since I've touched Linux&LibreOffice, but I only knew that's its a signature, for identifying the work is created by me. But soon I've been touching some law questions and ...
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2answers
129 views
GPG: Change expected card number
I have switched from a YubiKey 4 to a YubiKey 5. Both have the same GPG keys stored. After storing the key on the first YubiKey, I fetched my public key so GPG knows where to look for the private key. ...
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1answer
121 views
I use full-disk encryption. Should I passphrase-encrypt my private key(s) anyway?
Suppose I want to use GnuPG on a GNU/Linux laptop where I've encrypted all filesystems (except /boot) with LUKS/dm-crypt. Backups are encrypted client-side and stored on a physically secure server. ...
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1answer
415 views
Preparing to change over to new GPG-key - what to do with my old ones?
I've just created a new off-line GPG-key with a sign/certify master-key and two sub-keys - one for signing and one for encrypting. 5 yr expiration for the master, 2 yr for the subs. My master-key got ...
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28 views
Know the setting used in creating key pair in GNUPG4Win version 3.15
I am using GNUpg4Win version 3.15. For the last few hours I am trying to figure out what default settings are used for Cipher and Hash during key generation.
Basically I want to use AES-128, 3DES ...
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7answers
11k views
Is layered encryption more secure than long passwords?
The comments in this question debate about the added security of multi-layered encryption. There seems to be some disagreement, and I thought a proper question would be helpful here.
So, to provide ...
