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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15
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3answers
10k views

Checklist on building an Offline Root & Intermediate Certificate Authority (CA)

Microsoft allows a CA to use Cryptography Next Generation (CNG) and advises of incompatibility issues for clients that do not support this suite. Here is an image of the default cryptography settings ...
6
votes
0answers
17 views

I want trusted SMIME certificates for 3rd parties. Is this a reasonable configuration?

I want to send out SMIME certificates with my emails, and want to deploy the following PKI Root01 (All EKU, All Constrants, No Restrictions) PolicyInt01 (Internal applications, not trusted by 3rd ...
2
votes
2answers
26 views

Certificate pinning and the key distribution problem

I (think I) understand the concept of certificate pinning. However, I'm wondering if, in the worst-case scenario: is certificate pinning any more secure than the hierarchical trust model it is built ...
3
votes
1answer
39 views

Ability to determine which PGP public keys a message has been encrypted for?

Is it possible to determine, given a PGP message that you can already decrypt, to determine which other PGP keys that message has also been encrypted for?
1
vote
1answer
33 views

P12 private key vs private key file : what is more secure?

The question is a bit tricky because they don't have the same purpose but : Do both kind of file face the same security issue concerning private key protection : password strenght ? (PBKDF2 as both ...
3
votes
1answer
76 views

Clarification needed on CSR signing process

There doesn't seem to be a lot of in-depth information on the certificate signing process other than: Key Management Interoperability Protocol Usage Guide Version 1.2 (PDF) RFC 2986 - PKCS #10: ...
0
votes
2answers
26 views

Can revoked certificates be “lost” if the base CRL is updated before expiration?

Assumption Suppose I have a CA that issues a base and a Freshest CRL. I also understand the Freshest CRL to be a Delta of revoked certs in the base. I also understand that clients should pull the ...
0
votes
0answers
13 views

What is the minimum acceptable time for “Freshest CRL” to be updated?

I'm working with MSFT CA, and not sure if this behavior is the same across all CAs, but when I run certutil -CRL, the base revocation cert is updated weekly, and the Freshest CRL (the differential) ...
3
votes
2answers
101 views

Explicitly prohibit an intermediate CA certificate on OpenSSL

How do you explicitly not trust a particular certificate (especially, CA certificate) for OpenSSL? On NSS-based applications, one can install the cert with trustarg p: prohibited (explicitly ...
4
votes
2answers
85 views

How should I document my Public Key Infrastructure?

I'm preparing to document a 3 tier PKI (with multiple second level policy CAs) and want to create a document that is useful, technical, and not too overwhelming to the non-PKI expert. I suppose the ...
0
votes
0answers
12 views

What are some scenarios I would use MSFT Certificate Enrollment Web Services?

The Certificate Enrollment Policy Web Service and the Certificate Enrollment Web Service are made for non domain connected machines to retrieve certificates of various kinds. When setting this up, I ...
0
votes
0answers
25 views

Distribution of key by server

I have read that in asymmetric cryptography, a system admin can generate key pairs on the server. After that, the users will be given the generated key pairs and this is an efficient way of doing this ...
1
vote
2answers
60 views

multiple private keys for single public key

I am currently working in security in mobile ad-hoc networks I have several clusters, and I want from the cluster head to send some data encrypted with its public key ,to the cluster members. I assume ...
7
votes
6answers
3k views

Is Spoofing a CA signed certificate possible?

I had never thought about this situation before, I may be completely wrong but I am going to have to clarify it anyway. When a communication starts with a server, during the client handshake, the ...
2
votes
1answer
44 views

How do Client-specific keys and Certificates work?

I have clients that communicates with my server. Clients sends it unique id (guid) to server with its request over a secure https channel. Also to increase security I use my own private-public key ...
0
votes
1answer
35 views

public key formats [closed]

I have the following PEM format public key: -----BEGIN PUBLIC KEY----- MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDguwHaldTclMAFg1BQ45Q8DPIc ...
2
votes
1answer
3k views

What is the deal with Valicert SSL root certificates?

Does anyone know what the status of the "Valicert Class 2 Validation Authority" root certificate is or what's going on with Valicert in general? I've heard that that cert has been deprecated, no ...
1
vote
1answer
102 views

How do PGP keyservers synchronize the keys?

I want to know technical details about how public PGP keyservers synchronize the keys. If I send my key to one keyserver, how exactly does it "travel" to all the other ones? Who sends it to who and ...
2
votes
2answers
51 views

Does an alternative approach to PKI technology exist?

Currently all of the network is using PKI standards and we are facing many problems. I don't mean every time and if new technologies arise we will also have to face the same, but for my curiosity. ...
3
votes
1answer
4k 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
votes
1answer
43 views

What is the purpose of the CA-BUNDLE on a webserver?

So I purchase a certificate from DigiCert. The process goes like this: Generate private key and CSR on web server. Submit CSR to DigiCert. Get a signed certificate back as well as their root ...
0
votes
2answers
65 views

P12 - Extract public part (certificate) without knowing the p12 password

I would like to extract the public part of a revoked P12 which doesn't belong to me. I can't open it with KeyStore Explorer because I am prompted for the password, is it possible with OpenSSL ? The ...
1
vote
1answer
50 views

Why should I have my GPG key expire? [duplicate]

When creating a key pair using gpg it asks me for an expiration date: $ gpg --gen-key Please specify how long the key should be valid. 0 = key does not expire <n> = key expires ...
0
votes
0answers
33 views

How can I send an email using a GPG public key? [migrated]

I would like to send an email (on Windows), which I would like to encrypt using a GPG public key. I tried to use a Thunderbird plugin, but it requires both the public and the private key. But I have ...
2
votes
4answers
584 views

If a MITM has your public key and you are SSH-ing through the MITM, what is the maximum attack it can perpetrate?

Firstly, let me start by saying that I am not attempting to hack anyone or anything (not that I would know how or where to begin, if I were). For illustration purposes, let's call the primary key ...
-4
votes
2answers
214 views

Is “HTTPS” ~100% secure? [duplicate]

Assuming that we have a "green bar connection" to a website, e.g.: Is an attacker still able to sniff our traffic? How secure is a user from man-in-the-middle attacks when he has established a ...
1
vote
3answers
57 views

Secure tunnel set up in an office environment

Suppose I am a rogue employee and I want to syphon some sensitive data out of the office and I only have office internet access for this. My office internet access needs to go through a proxy server, ...
0
votes
1answer
86 views

Two-factor encryption model [closed]

Please some on help me to understand this "Are you ready for this? With the two-factor encryption model your data is protected two-fold. First, a unique key is generated, encrypted, and turned into ...
1
vote
1answer
1k views

Generating ECDSA certificate and private key in one step

Similar to how it can be easily done for RSA: openssl req -x509 -nodes -newkey rsa:2048 -rand /dev/urandom -keyout example.key -out example.crt -days 365 I'd like to generate a ECDSA cert/key in ...
1
vote
1answer
50 views

Message and Key Security

I'm reading Post-Quantum Cryptography, and in the page 106 in the beginning of the Section 3 it says: In this section we consider the message security (opposed to key security) of code-based ...
2
votes
2answers
70 views

How can I create my own public certificate using openssl?

I have a public key/private key pair i generated using two primes p and q. I now need to use openssl to sign and create the certificate. I heard req utility and wrote this from the man pages. openssl ...
4
votes
1answer
34 views

Mail Signing Certificate – What are the impacts when revocated?

Suppose I open a signed mail on 1st January 2000, signature is OK. What about this two cases : 1) If next CRL is to be published one week later, I found it strange that it is “probably” valid until ...
0
votes
0answers
13 views

why DH is unbreakable and what are the facts that leads to strong DH? [duplicate]

I am new to DH and learned the basic about DH working and suspecting it can be breakable by normal MIM , then how we can use DH in plain http for sharing secret. correct me if i am wrong.
0
votes
1answer
28 views

PKCS#12 File - security impacts when imported in Web Browser or Windows Store?

When a PKCS12 file is imported into a Web browser or Windows store the user is prompted for private key password. How does the browser or operating system manage this password? Is it secure?
0
votes
1answer
72 views

Sign PKCS#7 and verify PKCS#7 signature with OpenSSL

If someone have to transfer X.509 certificates in a single bundle, usually, it is recommended to pack them into PKCS#7. And content of PKCS#7 can be signed. OpenSSL allows to pack certificates into ...
12
votes
1answer
711 views

Relationship between RSA, Diffie-Hellman Key Exchange, PKI and X.509?

I am getting confused with RSA, Diffie-Hellman Key Exchange, PKI and X.509v3. I took a look of RSA's mathematics algorithm, it seems like a encryption algorithm, right? Generating public key and ...
3
votes
3answers
126 views

Corporate PKI - SHA1 deprecation

Here is the context. Suppose you have a corporate PKI with : AC_Root (offline in safe store - SHA1 signature) SubRootA and SubrootB (offline in safe store - SHA1 signature) SubSubRootC, SubSubRootD, ...
5
votes
1answer
105 views

PKI Installation

I must install a PKI in my organization. I work in a windows environment. I already set an offline CA. I must now install a subordinate CA. I have the choice between installing the subordinate CA on a ...
0
votes
2answers
56 views

Subordinate Certification Authorities and managed certificates

How many different certificates can a subordinate certification authority manage? Please, supply me also some reference. Thanks
9
votes
3answers
6k views

How to set up OpenSSH to use x509 PKI for authentication?

I do not mean simply putting the public RSA key of a x.509 certificate into ~/.ssh/authorized_keys - I'm looking for a way to set up a ssh such that x.509 certificates signed by a pre-defined CA will ...
0
votes
0answers
14 views

Certificate Validation [migrated]

I need to encrypt some data using the public key certificate available from one of my client's website. My question is aroung certificate validation? How can I validate this online certificate? I ...
4
votes
2answers
72 views

Verify digital signature without key public key in signature

When receiving emails, I sometimes see the following: -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I found an integer overflow in PHP, in the conversation of dates to "Julian Day Count" function. ...
1
vote
1answer
38 views

Does SSL/TLS have the feasibility of detecting malicious things during transmission? [closed]

As per my knowledge the current implementation of SSL/TLS does not have the capability to identify the data is malicious or not during the transmission or before encrypt the data. If its have , kindly ...
2
votes
1answer
318 views

CSR from IIS 8 and Keeping my Private Key a Secret

I've been trying to understand something. When you generate a CSR from IIS, how is the private key kept as a secret, or is it? Do CA's email you a certificate that includes your private key? Because ...
1
vote
1answer
25 views

Can a PKCS12 file be distributed over insecure channel?

Is the PKCS12 only as secure as the password protecting private keys ? Can I distribute the p12 file over an insecure channel ?
9
votes
8answers
518 views

Authencity of information displayed on an untrusted device

Suppose I have a (bluetooth/usb) device which needs to displays information on an external pc/phone. Is there a simple and effective method to garantuee that the information displayed hasn't been ...
4
votes
3answers
101 views

How can I create a unique identifier that can not easily be reversed?

I've been working on the design of a longitudinal study and one requirement is: all participants will have a unique identifier that is not reversible from the data storage/analyst side of the study ...
0
votes
1answer
67 views

PGP Key publishing on MIT PGP Public Key Server [duplicate]

I have a public pgp key, so that users can send me an encrypted message. Ofcourse, any user that wants to send me a message, wants to verify that the public key (s)he has, really belongs to me. From ...
2
votes
1answer
175 views

Openssl adding a telephone number or cell number to the distinguished_name

In the openssl.cnf file, I see fields like countryName, stateOrProvinceName etc which are typically present in the distinguished_name. Where can I get a list of fields which can be added to the ...
24
votes
4answers
3k 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 ...