A public-key infrastructure (PKI) is a set of hardware, software, people, policies, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates. In cryptography, a PKI is an arrangement that binds public keys with respective user identities by means of a ...

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138 views

Why/when would a CA make a generated public key available to the public at large?

I'm confused about this section in my CEH security exam training material: A CA is able to perform a number of roles in addition to the validation process outlined here. Some actions that a CA is ...
2
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2answers
71 views

Why not to use the same subordinate issuer CA for generating certificates that will be used for different things?

Microsoft has recommended my organization to use different subordinate issuer CAs in order to issue certificates that will be used for different things. For example, they recommend to use a CA for ...
6
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3answers
293 views

Why should my certificate signing request be signed by my private key?

Why should my certificate signing request be signed by my private key? Even if I obtain a bogus certificate out of someone else's public key, that is going to be useless, since in SSL the ...
3
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1answer
103 views

Designing a PKI environment

For our company I was given the task to design a durable, structured PKI environment for mainly client authentication purposes. We need a Root CA with a couple of Intermediate CAs, like this: ...
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2answers
214 views

How do I produce a CA signed public key?

I have a need to have somebody else encrypt secret data with my public key that I can then decrypt with my private key. I have produced an RSA private/public key pair with OpenSSL gave them the public ...
3
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1answer
56 views

What happens if an OpenPGP subkey gets compromised?

In my GnuPG keyring, I have a primary key for creating keys and three subkeys: two for encryption and one for signing. All of then have the same password. If a subkey gets compromised, is it possible ...
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0answers
28 views

Can there be two certificates with a same serial number in the world? [duplicate]

Recently I came across this odd question. I hope, Serial number is unique across certificates signed by a particular CA. So is there any chance that two different CAs sign two different certificates ...
1
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1answer
120 views

PKI management with easy-rsa

I recently setup an OpenVPN server with easy-rsa and have questions about certificate revocation: In the event that someone's private key gets compromised and I have to revoke the certificate with ...
2
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2answers
98 views

What exactly does `ssh -T user@domain verify` do?

The example I'm specifically thinking of is: ssh -T git@github.com verify Looking at the docs (man ssh) I can see that -T is the flag to "Disable pseudo-terminal allocation", but what implications ...
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1answer
187 views

How does letsencrypt's ACME work?

I found the technical paper on ACME's inner workings, but I still feel a bit confused about the ways Let's encrypt's Domain Validation works. From what I already know, verification can be performed ...
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0answers
36 views

PKI, one sub CA for each certificate type VS one for all the certificates type

I'm trying to set a PKI where I can find 3 types of certificates: A client certificate to use in HTTPS communications A web server certificate to use in HTTPS communication A VPN certificate to use ...
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2answers
70 views

PGP Key Signing Robot DKIM Verified Emails

It occurred to me that DKIM verified emails, from major players (e.g., GMail), could open the door to more modern OpenPGP robot key signing authorities. The idea would be to ask people to send a key ...
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1answer
47 views

Prevent credential roaming for certain accounts/certificates?

I want to use credential roaming in Windows 7, 8 and 10 for EFS certificates, so users can access their encrypted files from any computer they login to. However, some of these users will also have ...
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2answers
1k views

How secure is “Let's Encrypt”? [duplicate]

I just configured and installed a free SSL certificate from Let's Encrypt. It's great, and very easy to set up. However in this post-Snowden era, I was wondering how secure this really is. For ...
1
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1answer
30 views

Certificate binary matching

Is it an industry practice to do a binary matching of client public certificate when doing SSL with client authentication? I was thinking that if the client can successfully do the SSL handshake, ...
6
votes
1answer
150 views

Centralized key management for IOS and Android Code Signing

What is the best way for an enterprise to manage code signing certificates? The default seems to be that Apple and Android keys get stored by each developer on their machines. I see systems like ...
1
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2answers
71 views

Public Key Infrastructure: Sending data securely to CLIENT?

Ok, so been looking up public key encryption and using it a bit around some of my web applications. From some testing, I understand that the server contains two keys and sends the public key to the ...
3
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0answers
276 views

What are the use-cases for Hashicorp Vault PKI?

Hashicorp Vault has facility to auto generate server/client cert for authentication. https://vaultproject.io/docs/secrets/pki/index.html While it makes sense from certificate management point of view,...
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1answer
74 views

Is it safe to publish my development private key?

For my development environment, the following three SSL files allow me to access my application from https://localhost on my local machine. Private key: server.key Certificate signing request: ...
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0answers
68 views

Mysql SSL handshake: symmetric key exchange with CA or server key?

I have my MySQL database set up to require server and client identify verification, with both presenting their certificates signed by the same CA (mysql user was set up with 'require X509'). ...
20
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5answers
5k views

When can I commit a Private Key to source control?

That is to say, in what cases does it make sense to commit an unencrypted keypair to internal source control like SVN or Git? Related question that discusses an encrypted private key: Is it bad ...
1
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1answer
117 views

What Are Good Code Signing Environment Guidelines? [closed]

Take this scenario as an example: An organization has a few build servers that periodically check out source from a repository and builds everything. When a build finishes the binaries are code signed ...
1
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3answers
306 views

Using a stolen certificate on a server

Yesterday I asked the following question regarding what would happen if you placed a stolen certificate on your own server and edited the 'host' file so that the DNS name matched: Could a stolen ...
6
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2answers
569 views

Could a stolen certificate show as trusted?

I have recently started learning about PKI and have the following question/s. As far as I know a signed certificate contains the domain name of the server that the certificate will be placed upon. ...
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2answers
99 views

Public key - private key question

I have a query about public/private key encryption that I hope someone can answer. So as I understand it: Client connects to server and server responds with certificate Client pulls the public key ...
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3answers
55 views

Changing public key of someone to read and change messages that are encrypted to him

If I am able to change someone's public key, is it possible to alter the key to later read and change his encrypted messages in an easy way? Just remember I don't have his private key.
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3answers
1k views

Why is the subject's public key not used for encryption in SSL? [duplicate]

As far as I understand the workings of SSL - the client generates the pre-master secret and sends it to the server encrypted using the server's public key. Now, both parties perform some steps to ...
3
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1answer
58 views

Two-tier PKI without OCSP?

I am currently in the planning phase of a two tier Windows PKI using this deployment guide, and I am stuck concerning the use of OCSP and the online responder role of ADCS. The guide mandates that ...
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0answers
15 views

Partially Valid PKI certificate--But still we are able to login to our Application [closed]

User having a PKI card with an invalid PKI certificate (Among the two PKI certificates – One certificate is revoked (Damaged/ officially Cancelled) and another certificate is active)and try to login ...
2
votes
2answers
63 views

How does Certificate Transparance detect fake or forked logs?

I am trying to understand Certificate Transparency. Let's say I want to snoop on somebody's email. So I go hack or bribe a CA, have them issue a certificate for google.com, and then I present it when ...
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3answers
531 views

Does SSL/TLS provides non-repudiation service?

I understand that SSL/TLS provides confidentiality and integrity. But does it provide non-repudiation? I read in one book it does not. But I wonder why? What does it mean? If it means Alice can ...
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1answer
92 views

Why are pgp keys limited to a number of bits?

I am wondering : why does pgp keys have a fixed number of bits. They can be 2048,4096, but why not 56000 or 23 bits ? Is there a specification, or ISO, that was made to limit thoses Keys. Why? If a ...
0
votes
1answer
157 views

Generate RSA2 key in OpenSSH format in windows

I have to generate a key, RSA v2 in OpenSSH format. I am a bit confused. I am trying to generate it using Putty key generator. There I see an option SSH2-RSA and SSH1-RSA. So is SSH2-RSA the RSA2 key ...
2
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2answers
137 views

Is it possible to protect a DER private key with a password?

I want to write an API, based on OpenSSL, that can convert an RSA private key stored as DER to the PEM format. I'm just wondering if a DER key can be password-protected. I've searched the OpenSSL ...
50
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4answers
5k views

Can I sign a single character message with the RSA private key?

If I sign a very short message (0 or 1) with my private key (and the receiving side verifies the signature using public key), is this less secure than to send the sufficiently long signed message?
2
votes
2answers
68 views

What problem does PKI fix; how would someone “lie about their identity”? [duplicate]

What does having a certificate issued by a Content Authority protect against? In everything I've red (and watched) they teach it as "you are given the public key to communicate with Alice, but how do ...
0
votes
1answer
100 views

Reliability of Certificate Authorities and Certificates in 2015

I just happened to stumble upon this Article in Netcraft. The article claims that many of the major CAs have given out hundreds of Certificates to false organizations. Are there any truth to these ...
0
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2answers
113 views

Where are certificates used to prove identity and why aren't DNS responsible for the job?

I've been reading about how certificates are used to verify the owner of a public key in asymmetric encryption. Right now everything seems really theoretical to me and I'd like to know how this works ...
3
votes
1answer
89 views

What would happen if a public key server is compromised?

What would happen if in someway a public key server, let's say the MIT PGP key server, was compromised and some keys would be edited to an attacker's public key? Is this even possible? Would that be ...
3
votes
1answer
76 views

Best practice to verify data against a CA

Let's say that I have signed my public key with a trusted CA and the CA provided my with a signed certificate, and I want any client applications to verify against this certificate. The general ...
3
votes
1answer
141 views

Understanding the signing and verification process through a CA

I have been researching on this topic and I need to understand the exact signing and verification process when made through a trusted CA. From what I understand, this is how it works at a very high ...
2
votes
1answer
97 views

Correct way of signing and verifying a message

I have an object which I need to transmit to clients and I need the clients to know that I actually created the object. Obviously, this process involves in me signing the object with my private key, ...
3
votes
0answers
159 views

What is the openssl equivalent of using java's KeyPairGenerator?

I have been using java's KeyPairGenerator in order to generate public/private keys within a program so that I can encrypt and decrypt files(also using java encrypt/decrypt methods). I want to be able ...
4
votes
2answers
255 views

Why is openssl key length different from specified bytes

I realize this is rudimentary question, but I can't seem to even google diagnose it. Why is openssl key length different from specified bytes? For example when I use the command: openssl genrsa -out ...
5
votes
2answers
97 views

Data Integrity in PKCs

This is a simple question but one which greatly confuses me. When you have a PKC, the public key can be accessed by anyone. Therefore, doesn't this mean that anyone can encrypt data? My question is ...
0
votes
1answer
34 views

PGP Key Servers Verification Mail? [duplicate]

Why do existing PGP key servers not perform e-mail verification? Wouldn't it help the problem of authenticating of public keys? By e-mail verification/confirmation I mean a single e-mail sent to the ...
3
votes
1answer
54 views

GPG key expired on mykeyring, but still valid on keyserver

Can someone help me in explaining this: I have an old and expired GPG key, on my keyring the key lists correctly as expired: myself@mypc:~$ gpg --list-sig --fingerprint DDF70E72 pub 1024D/DDF70E72 ...
10
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1answer
226 views

Did D-Link's certificate revocation really only invalidate 1 day (of a six months long exposure)?

I'm trying to wrap my head around the OCSP revocationTime for D-Link's certificate. I recently answered another question and ended up drafting a timeline. That timeline is basically this: Jul 5 00:...
5
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0answers
147 views

Windows Certificate Services: Is it possible to enroll a SmartCard certificate AND have key archival?

I'm using ACOS5-64 Client Kit, I want to enroll for a certificate with key archival. I tried to do so by duplicating the SmartCard template and checked Archive subject's encryption private key option ...
4
votes
1answer
131 views

My OpenPGP private keys are set up with sub-keys. What happens if I revoke a sub-key and re-issue a new one?

I have set up my OpenPGP keys with sub-keys, following the general instructions laid out in "Creating the perfect GPG keypair." The general gist is that you create a "master keypair" which is not ...