PGP is short for "Pretty Good Privacy". It is a data encryption and decryption computer program that provides cryptographic privacy and authentication for data communication. PGP is often used for signing, encrypting and decrypting texts, E-mails, files, directories and whole disk partitions to ...

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35 views

Details related to the ZIP algorithm used in PGP message encryption [closed]

I am very new to PGP. PGP encryption works with hash function, asymmetric encryption, symmetric encryption and a zip algorithm (LZ77). What I know is that the zip algorithm is used to reduce the ...
1
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1answer
42 views

Using ECC for PGP-Master Key in combination with Yubikey

I acquired a Yubikey Neo last month. Now I want to use the Smart-Card functionality for PGP. I followed the official guides on the Yubico Website tested it with 2048 RSA Keys and it worked fine. But ...
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0answers
24 views

Sharing master cert and verifying certs with that [migrated]

I'm working on an application which has to download some files frequently. I thought signing files is a good idea. So first thing I thought to do is to create a master cert and somehow distribute it ...
3
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1answer
54 views

How to verify an OpenPGP key's ownership?

I've added the public key of Diceware creator (please use it as a practical example), I've added it by downloading diceware.wordlist.asc, and I didn't have his key and couldn't immediately find it to ...
3
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1answer
80 views

GnuPG - Problems with large RSA keys

I have read that GnuPG limits the size of RSA keys to 4096-bits because this could lead to problems with running out of secure memory. But in which operation is this the case? Generating the keys? ...
14
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3answers
774 views

Why is encryption (or signing) of long lines in E-Mails with PGP problematic?

I am using Thunderbird with Enigmail and OpenPGP to encrypt and/or sign E-Mails. On many occasions Enigmail complains that I have too long lines in the mail and asks how it should wrap them. However ...
4
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2answers
35 views

What do the terms used in OpenPGP keyserver SKS mean? (sig, sbind, sig3, exp2, Policy, …)

When viewing a key record in a public key server, such as this one, there are lots of keywords used: sig, sig3, exp3, Policy, sbind…). I understand that "sig" probably means a signature, but what's ...
2
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1answer
31 views

Multiple OpenPGP encryption keys signed by a single certificatation key?

Say I have several different email accounts and I want to use a different encryption key for each of them but still have them all certified under one identity. Is this a good idea and how would I do ...
2
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3answers
51 views

Chaining multiple PGP keys

I would like to know the practical limitations to contact chaining multiple peoples pgp key's in order to protect a file. In normal public key cryptography, four keys are required, public and private ...
4
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1answer
37 views

Do I need to revoke both my OpenPGP primary key and subkey?

After creating an OpenPGP key pair in GnuPG, if I list keys with gpg --list-keys, I get (GnuPG default): /someone/.gnupg/pubring.gpg ------------------------ pub 2048R/BC589B05 2015-07-15 uid ...
8
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1answer
133 views

What to do with a PGP/GPG key to which I've lost the private key?

I created a private key with an Android app I'm no longer using. I had uploaded the public key to the keyservers without setting an expiry date. I later deinstalled that app, and deinstalling ...
8
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3answers
889 views

Can I expose a passphrase-protected private OpenPGP key? [duplicate]

I have created a 4096-bit key-pair using GnuPG. Can I expose the passphrase-protected private key to an untrusted system? E.g. can I put that key in my Dropbox account or send it to myself as an ...
1
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1answer
20 views

Why has my OpenPGP key been duplicated on expiry change?

I've published my OpenPGP key publicly on the MIT key server. Later I realized I needed to set the expiry date to an earlier date than the one the (sub-)key was published with. I managed to do this ...
1
vote
1answer
32 views

Is it possible to assign different UIDs to subkeys for the purpose of having multiple identities?

Many people advocate generating new primary keys for each identity they wish to have. For example, creating one primary key and associated subkeys for workplace use, and a completely different ...
0
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1answer
53 views

Is there a way to change the creation date of a GPG/PGP cert

How can I modify the creation date of a GPG/PGP key? I can set the Creation-Date while creating a key. But can I change this Creation-Date after the key was created? I cannot find how to do this.
2
votes
1answer
102 views

How to send an encrypted mail only knowing the PGP fingerprint?

How does one send an encrypted email with PGP, when he only has the recipient's fingerprint? I am already sending emails using PGP, but I've just pulled a contact's PGP fingerprint who I need to ...
1
vote
1answer
36 views

What does the letter in an OpenPGP key's bits definition (like 4096D) denote?

I noticed that when looking at OpenPGP keys on a key server, the key's bits definition is usually followed by a letter, as in "4096D" for example. However, there are also keys with other letters than ...
0
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0answers
12 views

Risk to pgp secret keys with known cleartext/ciphertext? [duplicate]

There are a couple of schemes which encrypt IMAP message stores to yourself using GPG/PGP. Which makes initial sense and would keep casual snoopers from getting email. But it raises a question as ...
1
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1answer
26 views

Are PGP/GnuPG trust information transferred to key servers?

When signing a key X in the PGP Web of Trust model, I assign the key full validity. Other people who have my key in their key ring can regard X as valid as far as they fully trust me (owner trust). ...
18
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5answers
1k views

Considerations for long-term key storage (paper backup, media for vault storage)?

I'm reviewing our company's security procedures regarding cryptographic keys and master passwords, and also my private system at home. The key generation process is pretty much the same as that ...
0
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2answers
27 views

Is there a way to attack STARTTLS + certificate pinning probed from multiple places?

I just had this discussion on IRC and I have to admit I did not understand why other users were not convinced this would be enough... Let's say I would like to protect e-mails sent out from my ...
3
votes
1answer
34 views

Merge a second OpenPGP key pair into user id of other key

I have OpenPGP key pairs for two of my email addresses. When I created them, I did not know that it was possible to just add another user id to the first key pair. Then I found out it is possible from ...
2
votes
1answer
41 views

Cross-certification between worlds like X.509 and PGP?

Sometimes it can be advantageous to use existing trust relationships in one certification world - X.509 or PGP - to create trust in the other world. At the lowest level I can always take an X.509 cert ...
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2answers
53 views

Are these statements correct [closed]

Are the following three statements more or less correct: -To send someone an encrypted email basically entails having access to their public key (either smime or pgp). Thus for all practical ...
2
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1answer
26 views

Is it okay to omit the 'Version:' line in a PGP public key? [duplicate]

The software I use to generate my PGP keys doesn't include the 'Version:' line that most PGP software includes by default. Almost every public key I've seen begins like this: -----BEGIN PGP PUBLIC ...
4
votes
2answers
249 views

Sharing RSA keys between PGP and SSH protocols: Does this pose a security risk?

If I generate a PGP subkey that only has the authentication capablity and use this to generate an SSH keypair to authenticate Git for example, does this pose a security threat? When I do, should I ...
0
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2answers
52 views

Signing an OpenPGP public key that is not uploaded to a key server

Is there any point in signing an OpenPGP public key that has not been uploaded to a key server? In other words: does anyone except person A who signs person B's public key notice that the signing has ...
1
vote
1answer
68 views

How to change personal cipher/digest preferences of existing OpenPGP key in GnuPG?

The OpenPGP key contains a list of personal algorithm preferences (the meaning of the numbers can be decoded in RFC 4880): # gpg -a --export "foo@example.com" | gpg --list-packets | fgrep 'pref-' ...
2
votes
1answer
176 views

How to tell if my OpenPGP public key is self-signed?

I recently read: You should sign your PGP public key immediately after generating your public/private key-pair. And now I wonder how I can check whether I already did that. So my question is: ...
-1
votes
4answers
132 views

What mail applications use crypto?

I just read that everyone in the world can ready my mails (if intercepted in traffic by eavesdropping?). Also, it reads that current versions (book's from 2004 so I assume that new versions adopt ...
3
votes
1answer
92 views

How to decrypt email with revoked key in enigmail?

Is it possible to decrypt a message which is encrypted with a revoked PGP key? I still have the private key, but Enigmail doesn't show me revoked keys neither does automatic decryption. Edit: I ...
3
votes
1answer
149 views

toy OpenPGP encryption with manually generated keys

I've been playing around with OpenPGP encryption for a little while. Here are the steps I've followed: Generate an unencrypted public/private key pair in my keyring with gpg --gen-key. Dump the ...
5
votes
1answer
118 views

Master offline key, shared encryption/decryption key, unique signing keys?

I've read quite a few different articles on how to setup PGP keys with an offline master key. I own multiple YubiKey NEO hardware smart cards which I intend on using for PGP and as an SSH key. One of ...
0
votes
1answer
36 views

Risk of pgp-key to be compromised on smartphone [closed]

What risks to compromise my key, aside from the risk of the phone to be stolen, do I face when I use my private pgp key on a Motorola smartphone with the K-9-app? Can I mimimize the risk by using a ...
8
votes
3answers
576 views

Does OpenPGP encryption mean that not even I can see my data?

Say I have an email and I want to send it to someone else. I encrypt it with his public key. This ensures that only he can read my message. Does this also means that I won't be able to read it? If so, ...
3
votes
1answer
78 views

PGP Owner Trust Field & Signature Trust Field Distinction

I'm reading Cryptography and Network Security Principles and Practices (5th ed, p584) and reading about PGP keyrings, I'm a little confused about the differences between the owner trust field and the ...
4
votes
2answers
149 views

Is it possible and does it make sense to sign an E-mail with PGP and S/MIME?

After some research without any answer to my question, if it's possible and does it make sense to sign an E-mail with PGP and s/mime (?), I'm hoping to get an answer here. I know that, PGP and S/MIME ...
1
vote
3answers
96 views

Is it possible that to sign a message with a PGP key in a way that leakes the key

Alice provides a software for signing messages. The software runs in a airgapped enviroment. The software is given the message that's to be signed and the private key. The software then produces a ...
3
votes
1answer
96 views

What public GPG key do I have to publish?

I just created a master key and two subkeys. The first subkey is used for encryption, the second one for signing. Now I am wondering what public key do I have to publish on my website. Does is ...
5
votes
1answer
230 views

Can I check who can decrypt my GPG message after I encrypt it?

When I send, say, a great recipe for funnel cake to Alice and Bob using GPG, I can be pretty sure they will both be able to decrypt it. However, can I be certain, or prove after the fact, that they ...
2
votes
1answer
200 views

PGP key on smart card: why do I need a “secret key” on disk?

I have a YubiKey NEO on which I have the OpenPGP applet and I have a PGP key installed. I work on 3 different computers and I initialized the card on computer bob. I'm now at computer rob. Someone ...
1
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0answers
55 views

OpenPGP (RFC4880) - do you agree with my SimpleS2K (string-to-key) implementation?

Background: I'm writing a GPL Python OpenPGP to JSON parser which I'm testing on files generated with GPG 1.4.16. If given a passphrase, the parser will generate keys using the string-to-key methods ...
1
vote
1answer
88 views

What is the risk of using SHA1 in PGP email signatures?

SHA-1 is being phased out by a lot of major companies due to vulnerabilities. For example Chrome no longer considers it safe for public web PKI. Is it insecure to use SHA-1 for PGP email signatures?
2
votes
4answers
59 views

Is PGP or S/MIME useful when both servers are self-controlled?

With regards to encryption and preventing a 3rd party from viewing my emails (and ignoring validity/signing), is encrypting an email via PGP or S/MIME useful when I control my server and my recipient ...
4
votes
2answers
111 views

Do GPG and OpenSSH use key stretching on their keypairs?

Both OpenSSH and GPG can generate key pairs which are stored as files in well-known paths inside the user directory. A passphrase is always asked for during the generation process, which is then used ...
2
votes
1answer
138 views

Short OpenPGP key IDs are insecure, how to configure GnuPG to use long key IDs instead?

Short OpenPGP key IDs (with 32 bits / 8 hex characters) are subject to collision attacks. It is strongly recommended to stop using 32 bit IDs: Stop using 32bit key ids It takes 4 seconds to ...
4
votes
1answer
361 views

What are the security differences between SMIME email and PGP email? [closed]

Outside of key distribution, and specific to the technical details relating to encrypted email data (message body), what's the difference between SMIME and PGP? Example comparisons Security ...
5
votes
2answers
100 views

Why don't PGP keyservers enforce double-opt-in?

One thing that I found out when starting using PGP: When I uploaded my keys to the SKS keyserver, the keyserver did not take any action to verify that I am who I claim to be. Since a PGP key contains ...
1
vote
1answer
47 views

Using scrypt to encrypt data in a session variable

Let's say I want to store some data in the node's session, for example, like an authenticity token. Obviously I want to store it in an encrypted way if it's going in a cookie, then decrypt it on a ...
1
vote
1answer
56 views

PGP: Can I just upload my public part of encryption sub key to PGP server?

I'm a little bit confused here, since the best practice suggests that main key should be completely offline, so which key should I upload to the public directory? Here's what I have: main key (sign ...