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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openSSL Not Displaying all attributes
Here's a background of what I've done so far:
I've been able to add a CRL to a self signed certificate using OpenSSL (see attached). But I'm not sure how to create an X.509 certificate issued by ...
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1answer
1k views
Is your PGP passphrase used to decrypt an encrypted private key, or needed in conjunction with the private key to decrypt the message?
If the former, then if the private key can be used to digitally sign messages, why doesn't your client offer to encrypt this highly sensitive piece of data?
If the latter, then if someone had access ...
3
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1answer
585 views
how do extended validation X.509 certs work?
https://www.forumatic.com/ uses an extended validation cert. wikipedia.org's entry on extended validation certs says that a cert is known to be an extended validation cert if the OID in the ...
0
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1answer
318 views
URIs in the subjAltName X.509 extension
The subjAltTag extension for X.509 certificates can take in domain names, email addresses, URIs, etc. I was playing around with an X.509 whose subjAltTag had just a URI in it doesn't seem to work. ...
2
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3answers
314 views
why does the first certificate have a RSA public key in x.509?
Example from http://en.wikipedia.org/wiki/X.509#Extensions_informing_a_specific_usage_of_a_certificate
1st certficate - freesoft
2nd - CA thawte
Don't we use the RSA public key from the 2nd ...
8
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3answers
348 views
Difference between Certificate Authorities
I've been wondering for a long time about is. There are many certificate authorities having different types of certificates. But even certificates of the same security level cost a lot more with one ...
3
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2answers
457 views
What encryption schemes require two or 3 private keys to read a message?
I would like to encrypt some data so that it can only be read if two or three people use a private secret to decrypt the data.
What is the best / most modern way to accomplish multi-person ...
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1answer
86 views
valid intermediate certs not in browser
Say an X.509 cert is signed by an intermediate cert that's not in your browser. Maybe the root certificate is but not the intermediate cert. At that point it seems like a valid certification path ...
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4answers
1k views
What web browsers support OCSP stapling? Are the privacy and performance features the same?
OCSP stapling decreases the load on a PKI infrastructure's OCSP server by attaching a signed OCSP response to the target in a TLS connection. In addition it creates a more secure/private session ...
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2answers
290 views
X.509 certificate policies question
I asked another question about certificate policy mappings. This is a different issue. This is about Certificate Policies.
To quote from the X.509 RFC:
In an end entity certificate, these ...
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1answer
217 views
X.509 certificate policy mapping question
So I'm a little confused how X.509 certificate policy mappings work. So let's say the following depicts my cert chain:
root CA ---> intermediary CA ---> client cert
Would the root CA have a ...
5
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3answers
925 views
Why does OpenVPN require securely sharing certs with clients?
The ubuntu docs on OpenVPN have this part in the instructions:
Copy the following files to the client:
/etc/openvpn/ca.crt
/etc/openvpn/easy-rsa/keys/hostname.crt
...
8
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3answers
609 views
Is it safe to store a single symmetric key encrypted with several different RSA public keys?
For the field-based encryption of a database containing sensitive information, I was thinking of the following design:
Every user has a smartcard used for client certificate login.
After login the ...
3
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3answers
229 views
Public key system confusion
I read the following about PKI:
Using a public key system, a user may encrypt a portion of a document
using his or her private key. This message will later be decrypted by
the recipient using ...
10
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2answers
691 views
SSL fingerprint inconsistency: what does it mean?
I apologize if this is not the best place to ask my question on the stackexchange network, I couldn't figure out where to get enough attention and be relevant.
Facebook provides a SSL host, it can be ...
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3answers
904 views
Firefox detected an invalid SSL certificate
February 14, 2012 UTC:
Yesterday, I connected to a website of a VPN provider for which Firefox 8.0.1 on Windows 7 Ultimate x86-64 stated that its' SSL certificate is invalid. I saved the received ...
10
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3answers
807 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 ...
6
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2answers
418 views
Why would the downloaded certificate show a different end-date as compared to the same certificate when viewed online?
This is sort-of a follow-up to my previous question What fields in a suspicious certificate should I look at?
Chrome just presented the warning icon against the certificate presented by ...
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3answers
571 views
How can I share files with other individuals in the cloud in a secure way?
I would like to us a dropbox because it is easy and convenient.
But I want to encrypt the files with the public key of the intended recipient, so he will be the only one who can access the data in ...
5
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2answers
698 views
OCSP and CRLs: Specified in CA or client certificate?
Here's an example PKI setup:
* Root CA (offline)
* Issuing CA
* Client 1
* Client 2
I'd like to specify a CRL distribution point for CRLs generated by Root CA, and an OCSP URL for Issuing ...
0
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1answer
252 views
Enterprise Encryption Considerations
What are the different aspects to consider for Enterprise Encryption policy?
So far the resources I have are:
https://www.owasp.org/index.php/Cryptographic_Storage_Cheat_Sheet
...
5
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4answers
239 views
What fields in a suspicious certificate should I look at?
Looking at a certificate for a web-site (in Windows/Google Chrome) I see it lists the following fields
Version
Serial number
Signature algorithm
Issuer
Valid from
Valid to
Subject
Public Key
Basic ...
4
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1answer
325 views
Two certificates on smart card
I have a question regarding Swedish gov eID (but I guess it is a pki/smart card general question); Why is there two certificates/keys on the card?
Background:
In Sweden you can have a "citizen ...
4
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1answer
2k views
openssl verify signature
For S/MIME, I now know I can verify PKCS#7 detached signatures with:
openssl smime -verify -in detachedsign.pem -content content.txt
But what about non-MIME messages?
So if I sign the message ...
3
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2answers
166 views
Null content digitally signed message
IA technical specification I'm following requires me to send:
The Digital Signature must be in the form of a null content Digitally
Signed message (i.e. a PKCS#7 object containing the signature ...
7
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1answer
239 views
Why is there no Domain CA?
I was asked to deliver a signed SSL certificate for an IIS server for a client.
I have previously done this for the same client/domain before, so it start to seem like
an unnecessary expense to hold ...
12
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3answers
9k views
Expired SSL Certificate Implications
What are the security implications of an expired SSL certificate? For example if an SSL certificate from a trusted CA has expired will the communication channel continue to remain secure?
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2answers
282 views
How and when should I use OpenSSL for IT Security? How do I understand the output?
I'm discovering OpenSSL, and already used it to diagnose a faulty SMTP TLS connection, but I'd like to get a better / full understanding of the tool and how to use it.
What resources should I use ...
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3answers
3k views
What are the risks of self signing a certificate for SSL
Let's say I sign a SSL certificate for myself, and I'm not using a certified CA. What are the risks and/or threats of doing it?
13
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4answers
4k views
how digital signature verification process works
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 ...
16
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4answers
5k 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?
3
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2answers
402 views
How practical is a certificate's “basic constraint” property in protecting my HTTPS / SSL session?
Suppose a leaf node creates a certificate for a different domain, acting as a CA.
Do most popular frameworks, or SSL chain validation tools verify the constraints? Are there any I should be ...
6
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3answers
148 views
Guarding against rogue certificates
There has been a lot of news recently about certificates being falsely issued (due to the issuing authority having poor system security!). Apparently the targeted users were mostly Iranians, but it's ...
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4answers
4k views
Recommendations for a Certificate Management tool for Linux
A client is looking to roll out OpenVPN to all its mobile employees and will use certificates on both the server and all clients.
This creates a new challenge to manage all these certificates and ...
6
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3answers
316 views
Why are CA's signing keys available on the internet
I am not very knowledgeable about CA certificates, but I thought these things mainly said
"The public key for bank X is Y, and this is verified by CA Z".
Once you've bought this certificate, there is ...
10
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3answers
424 views
Multiple CAs signing a single Cert/CSR?
Just saw this suggested on Slashdot
So I've seen quite a few people wanting a switch to self-signed certs (who IMO mostly don't understand what making that secure actually involves), and an idea ...
4
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2answers
241 views
How are possible uses for X.509 (SSL) certificates denoted?
X.509 certificates can be used for servers, clients, email, code signing and more applications. http://twitpic.com/6gdxaq indicates that a certificate can have different of these 'capabilities' on it ...
21
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3answers
665 views
What is an SSL certificate intended to prove, and how does it do it?
If I get an SSL certificate from a well-known provider, what does that prove about my site and how?
Here's what I know:
Assume Alice and Bob both have public and private keys
If Alice encrypts ...
8
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3answers
492 views
Does the SSL encryption strength of a website really matter?
When looking to get an SSL certificate one is presented with a lot of options. For example lets take Network Solutions since they have a nice comparison chart.
Immediately there seems to be 4 major ...
3
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1answer
358 views
What kind of certificate do I need to be able to make and sign my own digital signing certicates?
At build time for a program, I would like to generate a new key pair, and create a certificate that will be embedded (securely) into the program. The purpose of the key pair is to digitally sign an ...
6
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2answers
232 views
Geographic equivilent of RFC 3161 (X.509 PKI Time-stamp Protocol)
First time poster here, hope to be around more often.
I'm in need of a cryptographically secure 'stamping' system that allows not only time but also location to be attached to data, while still ...
16
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3answers
1k views
What happens when an Intermediate CA is revoked?
Currently I'm working on a certificate manager that allows our product to securely connect to remote webservices (over TLS/SSL).
For security, we use Certificate Revocation List checking (or ...
10
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4answers
664 views
Why isn't OCSP required by default in browsers?
According to the following screenshot, taken from firefox-3.6.17-1.fc14.i686, Firefox has an option to fail closed when unable to connect to OCSP servers.
Can someone please explain why this isn't ...
10
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7answers
796 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 [not with free will, so e.g.: I'm "attacked"] a rouge DNS ...
8
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1answer
154 views
distributing files to VPN partners
suppose i've created VPN certificates for a certain VPN-RoadWarrior-Client, expressed in the files VPN-RoadWarrior-Client.key and VPN-RoadWarrior-Client.crt*, however VPN-RoadWarrior-Client is ...
6
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2answers
388 views
security of PKI, Certificates, certificate authorities, forward secrecy
I want to understand how certificates add to the security of information exchange.
Suppose i have a encrypted bidirectional connection between Alice and Bob, using a public key/private key pair. As ...
10
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3answers
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Computationally simple, lightweight replacement for SSL/TLS
Target hardware is a rather low-powered MCU (ARM Cortex-M3 @72MHz, with just about 64KB SRAM and 256KB flash), so walking the thin line here. My board does have ethernet, and I will eventually get ...
7
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1answer
551 views
Moving from a one tier to a two tier Microsoft Certificate Authority hierachy
Right now we have a single Microsoft Enterprise Root CA which issues certificates to our VPN users for two factor authentication. We're planning to extend use of the CA to issue certificates for RDP ...
8
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1answer
1k views
Renewing Microsoft Certificate Services Root Certificate
We currently have Microsoft Enterprise Certificate Server installed on a domain member machine which issues 1 year certificates to users for authenticating to VPN.
We'd like to start issuing web ...
11
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1answer
690 views
How would I implement “Broadcast Encryption”?
I have a stream that I want to encrypt for broadcast to 10,000 subscribers. I know I should encrypt this data using a symmetric key; and also intend that this symmetric key will be rotated every 30 ...
