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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1answer
223 views
Any reason not to use same key for multiple SSL domains on one server?
Assume I've generated a server key for use by Apache for SSL. The server will be handling several different domains that use SSL via unique IPs (no SNI).
I want to generate a CSR for each domain from ...
1
vote
3answers
306 views
Please recommend best-practices documents for sharing encrypted data with non-technical end-users
Is there one, or several, "best practices" documents which cover in clear simple language how to share data among a non-technical support staff and non-technical end-users at various organizations?
...
21
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3answers
621 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 ...
3
votes
2answers
252 views
Mitigations for Windows clients that don't support OCSP Nonces
Windows 7 clients (and older) don't support NONCES, a key feature used in securing the revocation check. Without a NONCE a MITM could replay a previously signed response and alter the validation of ...
6
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1answer
1k views
How does adding a random serial number improve a certificates' security?
This article says:
"Finding collisions is a tricky process, since it requires you to muck
with the bits of the public key embedded in the certificate (see this
paper for more details). Also, ...
2
votes
1answer
232 views
Is the Netscape SMIME extension still required in a certificate?
Every Windows 7 host has a Trusted Root certificate from Entrust that has the "Netscape Cert Type" extension (see image)
I'm comparing inter-operable S/MIME extensions and see a pretty diverse set ...
1
vote
2answers
98 views
S/MIME and Dual-use certificates
My assumption is that S/MIME almost always utilizes certificates as follows:
My certificate can be used to allow people to encrypt messages and send them to me.
My certificate (the same ...
4
votes
1answer
415 views
Can a certificate have multiple chains and multiple self-signed roots?
The following MSFT document has this paragraph:
All possible certificate chains are built using locally cached certificates. If none of the certificate chains ends in a self-signed
...
1
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1answer
303 views
What are attribute certificates? Why would someone partition a certificate by reason codes?
In "How Certificate Revocation Works" a brief mention of Attribute Certificate and Reason Code partition is made:
If validated by a client that supports partitioned and indirect CRLs,
the IDP ...
1
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1answer
1k views
Clearing IE temp files don't erase CRL history. How can this be purged?
Even after I purge all my Internet temporary files, I still see information when I type
certutil -urlcache
How do I purge this information?
1
vote
1answer
903 views
What are the OIDs (KU and EKU) necessary for Smart Card Authentication in Windows?
MSFT smart card authentication is listed in PKINIT RFC 4556 however I don't see any OIDs listed.
Based on this and this KB article the EKU section of the certificate should contain "Client ...
1
vote
1answer
398 views
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 ...
2
votes
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
votes
1answer
538 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
votes
1answer
298 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
votes
3answers
299 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 ...
3
votes
2answers
437 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 ...
1
vote
1answer
85 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 ...
5
votes
3answers
854 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
...
10
votes
2answers
641 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 ...
3
votes
3answers
223 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 ...
12
votes
2answers
357 views
Encryption and the “security time decay” of prior encrypted data
This question is on the assumption that any data once encrypted, may (eventually) be decrypted through
Brute force (compute power/time)
Exploits in the cryptography used
Theft of private keys
...
0
votes
3answers
879 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 ...
0
votes
1answer
250 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
...
10
votes
3answers
733 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 ...
5
votes
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 ...
5
votes
2answers
657 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 ...
5
votes
4answers
232 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
votes
2answers
235 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 ...
2
votes
2answers
1k views
What is an intermediate certificate authority?
What is meant by an "intermediate certificate authority?"
4
votes
1answer
307 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
votes
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
votes
2answers
155 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 ...
3
votes
2answers
271 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 ...
12
votes
4answers
3k 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 ...
6
votes
3answers
517 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 ...
10
votes
3answers
1k views
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 ...
6
votes
2answers
372 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 ...
6
votes
3answers
315 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 ...
3
votes
1answer
340 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 ...
8
votes
3answers
483 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 ...
9
votes
3answers
400 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 ...
3
votes
2answers
389 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 ...
5
votes
1answer
630 views
Thunderbird - what happens if Gmail SSL cert gets spoofed?
I use a good MUA: Thunderbird [to read/reply to my emails on Gmail].
So: what happens, if i go to a place, where is public wifi, and someone tryes to sniff my password/username/emails?
Questions:
...
6
votes
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 ...
10
votes
7answers
783 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 ...
6
votes
2answers
223 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 ...
7
votes
1answer
149 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 ...
7
votes
1answer
958 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 ...
7
votes
1answer
541 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 ...
