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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200 views

Certificate security in intranet environment?

We have this topology in our company: A new rule says that each document being sent by Outlook should be encrypted. We decided using PGP. We already have a certificate (self-signed). The problem ...
4
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1answer
443 views

Is OpenPGP encryption a valid replacement for SSL when passing messages?

I am writing an application that occasionally needs to transmit larger messages to other servers on the internet without allowing people to snoop on the traffic. The normal way to handle this is to ...
11
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2answers
2k views

Is it okay to widely share the RSA key fingerprint for a host?

When you ssh into a remote box for the first time or if the remote host's key fingerprint has changed (from what's stored in your known_hosts file) you get a warning and you are shown the fingerprint ...
5
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1answer
524 views

Which attributes of a X509v3 certificate are never really used?

Are there any extensions/extended key usage attributes of a X.509Certificate that are rarely or never used in practice? Either due to never being part of an issued certificate or because they are ...
11
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2answers
2k views

Are there really functioning quantum computers?

I saw this video on youtube on quantum computing. It says that a company called dwavesys has already made commercially available quantum computer. I checked on the website and it exists. I thought ...
3
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1answer
2k views

What are the Netscape Cert Type attributes? Why/when are they needed?

What are the Netscape Cert Type attributes in a X.509 Certificate and how are they different with the X509v3 extensions? Example: There is the Client/Server Extended Key Usage (X.509) but there is ...
1
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1answer
649 views

Why does the OpenSSH client on Mac OS X silently launch an ssh-agent for the user?

I'm confused by the difference in behavior of ssh clients I'm seeing on two different hosts. Just to be clear, this is the scenario: "macbox" OS X using OpenSSH_5.2p1 ssh client "sunbox" Solaris 10 ...
2
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2answers
1k views

Revoked certificate validation using past times

I'm working on XAdES implementation for Java, as such I require cryptographic implementation to be able to verify certificates in the past. Unfortunately I have problems verifying revoked ...
3
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3answers
133 views

Can the root of a system access to unencrypted data when using a double tunnel?

I connect to a DMZ gateway system (B) which is not secured. From this machine (B) I can connect to the final destination (C). A-->B-->C I created a ssh tunnel from A to B and forwarding the port 22 ...
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0answers
254 views

Verifying Authenticode signed executables and DLLs using OpenSSL API [closed]

I have installed openssl and now the rsa_test.c is running fine. What I want to do is: Open any exe or dll digital certificate. Extract the Thumbprint and PublicKey. The public key contains the ...
6
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2answers
863 views

ASN.1: ENUMERATED vs INTEGER

From the X.509 specs: CRLReason ::= ENUMERATED { unspecified (0), keyCompromise (1), cACompromise (2), affiliationChanged (3), ...
2
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1answer
131 views

Which .CER file format is more secure for purposes of an AIA record?

What file format is most appropriate or secure for the AIA record in a PKI certificate? The options I'm aware of are: DER encoded binary X.509 (.cer) Base-64 encoded X.509 (.cer) I also have the ...
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1answer
292 views

security issue on storing keys and certificate on token

I'm creating a sample USB token with Atmega64. As I have to store both the public and private key and the certificate on my token is there any important security issue that I should worry about, ...
3
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2answers
626 views

Distributed XAdES-X and XAdES-A signatures over multiple documents

As the standard is not completely clear in this matter, I'm trying to found out if the XAdES standard (ETSI TS 101 903 v1.4.2) describes distributed case in which the SigAndRefsTimeStamp element or ...
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1answer
168 views

What keys are involved in an X.509 certificate?

I'm trying to examine some instances where an X.509 certificate uses public and private keys for a paper I'm going to write. However, the only thing I have explicitly seen so far is in one of the ...
3
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2answers
2k views

x.509 CRLs: next update?

An X.509 certificate revocation list contains a field specifying when the next such list is expected to be issued. I'm trying to figure out the importance of this field...I know that sometimes ...
5
votes
3answers
1k views

Digital Signature and Verification?

AFAIK , When Alice wants to write a message to Bob -- she uses Bob's public key and encrypt the message - and then Bob - using his private key - use to decrypt it. So public key is used to decrypt ...
7
votes
2answers
6k views

How is an X509 certificate signer verified?

Lets say I create a self-signed X509 certificate A and use it to issue certificate B. I put certificate A in my trusted root authorities so that all certificates signed by it are accepted. My question ...
495
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3answers
245k views

How does SSL/TLS work?

How does SSL work? I just realised we don't actually have a definitive answer here, and it's something worth covering. I'd like to see details in terms of: A high level description of the ...
6
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3answers
680 views

What risks would exist in transmitting an encrypted PKCS12 via Https

I have a scenario in which I would like to automate the deployment of client certificates generated by an issuer I control. The approach I am considering is given below, and I would appreciate ...
4
votes
2answers
184 views

Using a verified certificate to sign others

This relates to PKI and certificates generally but websites more specifically. Could you get a verified certificate from a CA that is signed and fine for use, and then use it to sign your own ...
4
votes
1answer
79 views

Standards for CA cert revocation and time-constrained cryptographic algorithm parameters

I'm working on software that will be in use for foreseeable future (15 years+) that will need to validate XAdES-A signatures (long term archival, similar to PAdES-A, but for XML). That means, it will ...
5
votes
1answer
107 views

Is it possible to have multiple key lengths in PKI?

Is it possible to have multiple key lengths in a PKI? For example, use a 1024-bit key for the issued certificate, a 2048-bit key for the intermediate certificate, and 4096-bit key for the root ...
3
votes
1answer
222 views

CMC (RFC 5272) compatible CA server

I need a CA server or any tool that supports Certificate Management over CMS (CMC) format, described in RFC 5272 (RFC 2797). I need a possibility to generate different Full PKI requests and responses ...
3
votes
1answer
102 views

Within a CSR, is there a field to have the MS PKI server change the default cert filename

I'm not intimately familiar with MS PKI, but it was a question that came up in a discussion for an issue a coworker is having. When you input the request fields manually on a PKI server, the cert ...
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7answers
4k 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 ...
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3answers
2k views

RSA encryption : How to create “.arm” certificate file for Public key?

I am required to store a certificate as ".arm" file only for a public key that is intended for use in RSA Encryption. I am currently able to generate the public key as ".key" file. P.S I am new to ...
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4answers
8k 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 ...
2
votes
1answer
141 views

Curious about best start for autoresponding Certificate Authority (CA)

I am just getting started trying to implement some internal PKI ideas, where my app would need a cert to 'sign' messages. Since this is all completly internal, we have some degree of trust, and I ...
2
votes
3answers
437 views

Transfer Client Certificate

What, if anything, could or would be embedded into a client-side certificate that would prevent it from "working" when transferred to a new client machine on a new network? Being unfamiliar with the ...
0
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1answer
297 views

Can I export my digital certificate to this emtec usb

It is said here http://www.emtec-international.com/sites/default/files/s530_aes_en_0.pdf 2048 bit RSA module: ready for PKI application SHA256 data hashing: ready for digital signature Does it ...
5
votes
1answer
2k 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 ...
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4answers
15k views

How are Chrome and Firefox validating SSL Certificates?

How are Chrome and Firefox validating SSL Certificates? Are they requesting data from an SSL certification website, like GeoTrust, to validate the certificate received from the web server?
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votes
3answers
727 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? ...
6
votes
4answers
3k views

Can an intermediate CA be trusted like a self-signed root CA?

Is it possible within the limits of the X.509 specification to mark an intermediate CA as trusted for a specific purpose, e.g. to verify a VPN, HTTPS etc. server key, just like it would work with a ...
2
votes
2answers
99 views

Does it make sense that OCSP returns state for the signer CA itself

I have seen an implementation that in signature verification time searches for OCSP responses signed by the CA validating the status of the CA itself, so my question is if somewhere (maybe RFC2560) ...
7
votes
4answers
1k views

Alternative to “web of trust”

Let's say I have an SMIME platform where I want to easily establish trust across the entire world for a particular purpose, for example for sharing valid financial information. I think that a ...
7
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2answers
11k 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?
3
votes
2answers
173 views

In practice, does crypto software accept a *.com or or even a *. certificate?

Assuming this will be done with your own PKI, and not a public trusted CA. Considering that *.sub.domain.com is valid, and so is *.domain.com is valid, is it technically possible to issue *.com and ...
3
votes
2answers
496 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 ...
3
votes
1answer
521 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
192 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 ...
8
votes
1answer
3k 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, ...
5
votes
1answer
13k views

What is updated with “Update Root Certificates” enabled? What is the equivalent in Windows 2008R2?

What root certificates are/are not updated when the following checkbox is checked? Additional questions If I manually remove a root certificate, will this service replace that very certificate? ...
0
votes
1answer
610 views

How do I constrain Windows Smartcards for AD Authentication so that “anyExtendedKeyUsage” is not implied?

This document describes how there are 3 ways to constrain a SmartCard certificate The Enhanced Key Usage field defines one or more purposes for which the public key may be used. RFC 5280 states ...
2
votes
1answer
4k 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?
2
votes
3answers
1k views

What is the most secure way to do OCSP signing without creating validation loops?

I'd like to enable the most secure OCSP validation that Windows 2008 SP1 and newer support. Based on the following information, am I required to implement id-pkix-ocsp-nocheck on my OCSP ...
2
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1answer
1k 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 ...
5
votes
1answer
2k 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 ...
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1answer
5k 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 ...