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Questions tagged [public-key-infrastructure]

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 certificate authority (CA). There are three main categories of PKI: Web / SSL certs, corporate networks, and Government ID / ePassport.

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9
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3answers
15k 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 ...
0
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1answer
282 views

Should CRLs be published for Standalone Offline Root CA?

I'm setting up a two tier PKI Hierarchy in our Windows Server 2012 R2 domain. A number of tutorials suggest that the root CA should publish its CA certificate and CRL in Active Directory and via HTTP,...
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2answers
92 views

Signing webhooks with asymmetric keys

I want to sign webhooks from my web service with a JSON Web Signature (part of JWT standard), ideally using asymmetric keys (so, using RSA or elliptic curve cryptography). What is the recommended or ...
0
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1answer
385 views

How to automate publication of CRL and CRT files to CDP and AIA location?

I'm setting up Two-Tier PKI for the first time in our Windows Server 2012 R2 environment and I've read several tutorials on setting this up. Some of the methodology is very different, but I've chosen ...
1
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1answer
485 views

PKI - CRL and OCSP

I've done quite a bit of reading about PKI in ADCS and CRL/OCSP, but I can't seem to find an answer to a small couple of questions I still have: It is clear to me that even with OCSP in place, you ...
0
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1answer
52 views

Asymmetric Encryption + Signature workflow

Let´s say that Alice wants to send an encrypted message that only Bob can read, plus confirm that Alice is the person that wrote that message. What is the procedure that will take place? When I see ...
26
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3answers
60k views

How to get public key of a secure webpage?

How can I get the public key of a webpage like verisign , etc. using HTTPS protocol?
2
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1answer
333 views

One GPG key with multiple user identities for my career?

I am trying to work out what is the best approach for managing GPG keys over my career when I change jobs. My understanding is that there are two ways this could be done: Have one main/master GPG ...
3
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1answer
309 views

What happens to PKI once quantum computers can break encryption?

They say that public key infrastructure or PKI uses very complex encryption. What if that encryption breaks one day when quantum computers complete? What if they decrypt all private messages and data? ...
2
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1answer
67 views

How common is it for CAs to issue end entity certificates with Extended Key Usage marked as critical?

Does anyone know whether it is common for CAs to issue end entity certificates, which can be used as client certs (possibly among other purposes), with the Extended Key Usage (EKU) extension marked as ...
2
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1answer
99 views

Certificates for autoscaling internal networks?

A public website with an SSL certificate makes use of a certificate and CA in order to establish trust between the server and client. How is the same thing typically implemented on private networks, ...
4
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1answer
81 views

Under what conditions is the Client trying “the next” CRL Distribution Point?

We've got a scenario where the CRL is distributed to 2 different Locations. One ist accessable from a private network and not from the internet. The other one is asseccable from the internet but not ...
2
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2answers
89 views

File integrity assurance

I have the following scenario : Two parties want to exchange files. First party publishes a file on a secure server First party sends to the second, a hash of the file in order to be able to verify ...
0
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0answers
27 views

Whether cipher suites is related to public key certificate? [duplicate]

I want to use TLS version 1.2 and Authenticated Encryption with Associated Data (AEAD). Can a public key certificate obtained from a certification authority specify which of the ciphers I can use? ...
1
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0answers
114 views

Get S/MIME from Digicert, store in escrow on on-prem CA

I'm trying to crack the following nut: I have a contract with Digicert for S/MIME certificates for my org. Digicert allows to use their API for cert issuance. Unfortunately I can't let users self-...
10
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1answer
7k views

Difference between key encipherment and data encipherment?

In the context of SSL/TLS certificates, what is the difference between key encipherment and data encipherment? What are some examples that highlights the difference?
54
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4answers
90k views

How does the digital signature verification process work?

I am not able to understand that how the digital signature is verified. I know that digital signature will be attached to the message and sent by sender to receiver. then receiver uses the public key ...
0
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1answer
174 views

Signing JWTs with server's SSL/TLS certificate

I have a server that needs to sign JWTs asymmetrically. I can either generate a new public/private keypair or re-use my keypair used for my server certificate. Is there any concern about re-using my ...
0
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1answer
103 views

truststore and intermediate certificates

We have a situation where our on premise product talks to a third party external API over SSL. This API has a certificate which is issued by an intermediate. We use the default java cacerts truststore,...
10
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1answer
3k views

Manually walking through the signature validation of a certificate

Since I am not too familiar with the Web of Trust and Public Key-Infrastructure I decided to learn about it by following the signing chain of a X.509 certificate issued to CN=*wikipedia.org (Serial ...
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2answers
6k views

Does SSL/TLS provide 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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2answers
908 views

List of PKCS7 certificate file extensions

RSA (the company) devises and publishes the public key cryptography standards. In those standards, PKCS #7 is a standard which defines how to encrypt and sign messages using PKI. PKCS#7 defines a ...
10
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2answers
15k views

Cryptography behind chip based credit cards (smart cards)?

Why are chips safer than magnetic stripes? The answers to the above question explain that the chip based cards can not be cloned as the "secret number" is embedded in the chip and protected by the ...
66
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4answers
45k views

How to check if an SSH private key has passphrase or not?

Let's say I have access to the private portion of an RSA key-pair. How can I check if this key has associated passphrase or not?
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4answers
218 views

Do large companies use multiple public-private key pairs?

If I were to create a website I would then naturally generate a public-private key pair. The public key is published and the private key is kept private on the server. If the website has not a lot of ...
30
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9answers
10k views

Can a HTTPS connection be compromised because of a rogue DNS server

If I'm visiting (just a desktop PC, client side) a site that has a valid HTTPS cert/connection, that can it be compromised if I'm using a rogue DNS server (not deliberately, I'm concerned about an ...
7
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2answers
4k 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 ...
2
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2answers
248 views

Maximum number of certificates generated by a CA

What is the maximum number of certificates that can be generated from a CA? The use case is a VPN using certificate authentication and I would like to know what is the theoretical number of unique ...
0
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1answer
350 views

More clarity on Certificate, public key, hash

I'm new to this certificate and public keys. So I've a certificate. I exported as .pem. I opened it in textEdit and it looks like the below. I've used below command to see what this certificate ...
41
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2answers
37k views

4096 bit RSA encryption keys vs 2048

Where do 4096 bit RSA keys for SSL certs currently stand in terms of things like CA support, browser support, etc? In the overall scheme of things is the increased security worth the risk of 4096 bit ...
0
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2answers
433 views

How to approach 2 tier PKI RSA Root CA with subordinates that should support ECDSA

I have a situation for which I am not sure how to approach it. Basicialy I need to find out if it is possible how to issue ECDSA Certificates with a RSA Root Certificate. Is this possible? and how ...
0
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2answers
118 views

Is the root certificate issued from one Certificate Authority is same for all the requesting organisation?

Let me please explain the question a bit more through an example: There are lots of companies who have their certificates signed by Verisign (or any CA). I understand that Verisign signs these certs ...
0
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0answers
26 views

How related SSL/TLS to PKI? [duplicate]

It is not clear, how SSL/TLS related to PKI? It seems, PKI is part of SSL/TLS, but I'm not sure. Any clear explanation?
1
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1answer
92 views

Does the key size have an effect of the size of the public key and signature

If I have a 2048-bit RSA and a 4096-bit RSA key is my signature and public key smaller when I use a 2048-bit key vs a 4096-bit one ? (In bytes)
73
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6answers
60k views

How does PGP differ from S/MIME?

Is S/MIME an abstracted system for general MIME type encryption, whereas PGP is more for email? Why would I want to choose one over the other, or can I use both at the same time?
1
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1answer
81 views

Active Directory Certificate authentication trust

When setting up Smart card authentication you publish that Intermediate/Sub CA to the NTAuthCertificates object in Active Directory and certificates from that CA will now be OK for certificate ...
4
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1answer
746 views

ECC for future IoT devices?

Elliptic Curve Cryptography(ECC) is one of the powerful cryptographic methods that requires less computational effort. IoT requires a cryptosystem that secures smart services and applications (5As i....
5
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3answers
293 views

Risks of explicitly trusting SSL certificate vs relying on certificate chain for validation?

I'm working with a client that is manually importing our (publically signed and issued by a well known intermediate CA) SSL certificate onto their client systems. I believe they are doing this ...
4
votes
1answer
961 views

How can I add a custom domain to an SAN for a certificate for consul domains like active.vault.service.consul?

Say one has a service provided by Consul, for which active.[name-of-service].service.consul is the link it provides to the active host leader for that service. How would I properly set up TLS to that ....
2
votes
1answer
74 views

Standard practice for managing expired and revoked certificates used for signatures?

Curious to know what the standard practice is to maintain old/revoked certificates that were previously used to sign documents that must be verified in the future. For example, suppose there is a ...
1
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1answer
87 views

Why can I use 2 different private keys to connect to my SSH server storing only 1 public key?

On my server ~/.ssh/authorized_keys contains only 1 public key. However, I can connect to it using 2 different private keys. One private key looks like this: -----BEGIN RSA PRIVATE KEY----- ...
1
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2answers
86 views

Can Asymmetric encryption be used instead of modern authentication strategy?

Assuming that I have a way to associate a combination of public private key encryption with real people/user. The private key is stored on the device of the user. User have to communicate with some ...
44
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5answers
20k views

Are there technical disadvantages in using free ssl certificates?

Note this question is related, except this one is about free SSL certs. There are providers who are offering totally free entry-level SSL certs (like StartSSL). I was wondering if they are ...
0
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2answers
51 views

Can certificate signing requests be stored at the server to prolong existing certificates?

I want to build a PKI (public key infrastructure) to host certificates for users. My use case is, that I want to use the certificates for e2e encryption between the users. Users must be able to ...
1
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1answer
182 views

OCSP, CRLs, crlset - Revocation Delivery and Attacks

OCSP responses have a 'nextUpdate' field, which is the expected time for the new revocation update and that the current revocation can be considered valid. The revocations can be cached by the ...
19
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6answers
37k views

Extracting the PGP keyid from the public key file

Is there a way via an CLI tool or some kind of API to extract the PGP key ID from the PGP public key block? I found the hexa value of the key in the binary file, but I guess the position is based on ...
7
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2answers
2k views

Custom data in SSL certificate

I am looking for a way to add extra, custom data in a SSL server certificate issued by a standard CA. Is this possible? I want to get a SSL server certificate issued by a standard CA, so that it'll ...
2
votes
2answers
78 views

Security Appliance Key Generation

For devices like decrypting HTTPS proxies, there is often a built-in mechanism for generating a key-pair and CSR. An admin can then have their in-house authority sign the CSR with a subordinate CA ...
1
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2answers
149 views

Using PGP to answer account security questions with PKI

Security questions are well known/widely considered to decrease security or otherwise create more problems (e.g., remembering gibberish), but sometimes I am required to have and answer them anyway. ...
4
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3answers
3k views

Self-signed cert - how it works

I am new to SSL / digital certificates / signatures. What I know is that a digital signature must be verified/decrypted using the public key. So a cert that is signed by a CA must be verified/...