1
vote
1answer
22 views

What happens if my signing subkeys are compromised?

Let's say my subkeys are compromised, but my master keypair is safe and secure, so I revoke the old subkeys and issue new ones. With encryption keys, the results are pretty clear: I can still decrypt ...
0
votes
0answers
9 views

Is it possible to use certutil to export multiple certificates from a local client machine store, to a .p7b file? [migrated]

Is it possible to use certutil to export multiple certificates from a local client machine store, to a .p7b file? Scenario: We have a few legacy certificates based on some legacy templates (2012 R2). ...
1
vote
1answer
56 views

Are SSH keys and PGP keys the same thing?

I have a 3072 bit RSA key that I generated for use with SSH. Can this key-pair be used with PGP/GPG, or do I need to generate a new pair of keys separately for use in email encryption? Are the two ...
0
votes
1answer
28 views

Is there any benefit to providing multiple types of public keys?

Say I have a page on my website which lists public keys to be used in case people would either allow me access to a server, or send me encrypted information. Is there any benefit to me providing ...
3
votes
2answers
208 views

Export non-extractable private key from Keychain on OS X

I have a PKI certificate in Keychain Access.app on OS X 10.9, together with the private key. The manual page for /usr/bin/security indicates that there is a -x option for security import to specify ...
0
votes
0answers
63 views

How can I generate some public and private keys on both sides with low overhead?

We have an Authority Center (CA) generating some public and private keys for each client (more than one pair for each client). One method for sending keys to client is sharing a secret key between CA ...
0
votes
1answer
44 views

MITM protection, key distribution

I want to make sure each of my apps users only get their own data, and that nobody tampers with it or sniffs it in a MITM fashion. Encryption of everything should be the solution, right? But how do I ...
2
votes
1answer
131 views

Bastion host that allows jailed users to SSH but protects private key

Basically, I'm trying to let the user use a private key without having read access to it. Use case: Employee needs to SSH to a server in the data center. There is 1 private key for all servers, ...
2
votes
1answer
55 views

Utility of multiple signing subkeys when we're restricted to a single encryption subkey in GnuPG (PGP)

As I understand it, GnuPG allows the creation of multiple subkeys, but multiple encryption subkeys are problematic because it's not clear which encryption subkey someone should use when sending a ...
1
vote
1answer
48 views

When does S/MIME require the other party's certificate and when is their key enough?

Trying to understand S/MIME implementation, I see that sometimes you must have the other party's certificate, and sometimes its enough to just have their public key. I'm confused as to when you need ...
1
vote
2answers
230 views

How to maintain security and trust with a PGP keypair for a team or group of people?

I've seen many instances where a company or organization generates and uses a PGP keypair for a team or group of people. Most likely they all have a copy of the private and public keys on their ...
1
vote
0answers
226 views

Import securely RSA private key through PKCS#11

I have a cryptographic device that supports the following mechanisms: How I could securely import RSA private key into it? Because there is no support for wrap/unwrap using symmetric key is there ...
6
votes
3answers
1k views

Managing and storing lots of SSH keys in the cloud

I have a pool of cloud servers (~50) that need to talk to many other remote cloud servers (~4000) using SSH. Each remote server has its own SSH key, so we need a place to store all of these remote ...
1
vote
1answer
385 views

How to process or manage Key-Encryption-Key using HSM?

Let's consider two Encryption keys: 1.Data-Encryption-Key(DEK) 2.Key-Encryption-Key(KEK) KEK will be securely stored in HSM, which will be encrypted using master key. Data Encryption Key will be ...
3
votes
1answer
115 views

Can we build a key exchange protocol without certificates?

Assume that the server and the client both has some secret key K. Is it possible to have a key exchange protocol with authentication between them such that MITM attack cannot hold and if the key is ...
2
votes
1answer
1k views

How do I share my S/MIME public key?

I have setup S/MIME encryption for my email address, and I'd like to allow people to download the public key from my website, rather than having to first receive an email from me. I want the public ...
6
votes
1answer
146 views

public key distribution from a central server

I'm trying to code up a encrypted communication program. Originally I was thinking that I would use public key cryptography and then I would keep the public keys in a database where users could query ...
3
votes
2answers
172 views

Verifying the authenticity of a public key without manual intervention?

In RSA encryption it is said that ensuring the authenticity of the public key can be as important as the protection of the private key. An effective way of doing this is to have key custodians ...
3
votes
1answer
156 views

Design of system based on HTTPS, Client Certificates and custom CA

I have the following system: 2 application servers. At the beginning is installed the first server and later is installed the second one. A client access from a browser to both servers Application ...
1
vote
1answer
179 views

How to have Thunderbird include a root certificate?

An eMail signed via S/MIME also contains the X.509 certificate chain containing the public key in order to directly verify the signature (assuming its issuing CA is deemed trustworthy). The chain does ...
0
votes
1answer
892 views

What key sizes are allowed within TLS if the DHE_RSA is the only key exchange allowed?

Can I make assumptions about minimum and maximum key sizes if all I know about a TLS server is the fact that it uses DHE_RSA for key exchange? Can the server be configured to use weak key sizes for ...
-2
votes
1answer
651 views

GPG advantages / disadvantages, is it useful or secure? [closed]

I thinking about GPG, is very widely used, but is secure? Why and where we using GPG? I found an article from 2002, but is very old.
146
votes
7answers
12k views

How do certification authorities store their private root keys?

Knowledge of a CA private key would allow MitM attackers to transparently supplant any certificates signed by that private key. It would also allow cyber criminals to start forging their own trusted ...
21
votes
3answers
2k views

What's the common pragmatic strategy for managing key pairs?

I have a small number of different workstations (plus client devices like iPhone) that I use for to connecting to numerous servers using SSH. Originally when I learned about PKI, I created a single ...
20
votes
6answers
2k views

Shouldn't GPG key fetching use a secure connection?

If I run this for example: gpg --keyserver hkp://keyserver.ubuntu.com --recv-keys 0xFBB75451 then does the importing occur in a secure way? I mean does it go over only secured connections? (HKP?) ...
9
votes
2answers
399 views

PKI solution vendor selection

What would you look for in a (X.509-) PKI solution, and why would you look for that, given the following constraints: Available programming/sw-engineering know how is limited (ie, "OpenSSL with a ...
7
votes
3answers
854 views

What are the pros and cons of outsourcing an organization's PKI?

I am looking for the pros and cons of outsourcing an organization's Public Key Infrastructure (PKI). I understand that the answer to whether or not to actually outsource is going to depend on the ...