7
votes
2answers
261 views

How can we revoke all ssl certificates issued for our domain?

After having the hostmaster@domain.com email compromised, we found that someone issued a Domain Validated SSL certificate for our domain. Now we want to have all such certificates revoked. Is there ...
1
vote
1answer
34 views

How to safely renew user and CA certificates in a PKI

I am currently developing my own PKI where x.509-client-certificates are issued by a public server. At the moment, the CA-public key is distributed with the binary and there are no routines for ...
2
votes
2answers
54 views

What's the mitigation strategy for when a CA's private key is stolen?

I'm new to SSL/TSL and was wondering if you could walk me through the following scenario. Scenario Let's say I am one of a thousand websites that has a certificate signed by some certificate ...
2
votes
1answer
54 views

Is there any mechanism to audit which signed certificates are unrevoked?

We are currently using EasyRSA and OpenSSL to manage our user VPN certificates for OpenVPN. The process we have in place currently is: User generates a CSR on their laptop and sends it to us to sign ...
3
votes
1answer
49 views

What crypto prevents & detects “invisible” CAs? (e.g. in X509v4)

For this question, I'm calling an "invisible CA" one that Is signed by a root ca and exists as a 2nd or 3rd tier Is valid, not expired or revoked Has a different Public key than one that is ...
0
votes
2answers
30 views

determine X.509 certificate class

I am very familiar with OpenPGP but don't even use X.509 / S/MIME. I know that there are several classes for certificates (from email check to personal ID check). I would like to know how you ...
1
vote
1answer
38 views

Are “Certificate Templates” used only as a “Template” or do they validate a certificate request?

I'm trying to learn how Microsoft Certificate Templates interact with a certificate request, and can only guess that they take on one of the two/three forms: They simply help the client create a ...
0
votes
1answer
27 views

Temporarily suspending a Certificate Authority's Certiticate

The PKI RFC talks about revoking or suspending certificates. It also talks about revoking CA certs. However, I could not find anything about whether a CA or a Sub CA's certificates can be revoked or ...
2
votes
1answer
78 views

How do I get a third-party-signed ssl client certificate?

I've been given a requirement of providing a client certificate to authenticate between two application's web services. The other application (that I don't host) is requiring an SSL client certificate ...
4
votes
3answers
141 views

From a trust perspective, is renewing a CA certificate the same as trusting a sub-CA?

I'm trying to understand the validation logic that would occur in the following hypothetical scenario An unpatched XP user who trusts a list of root CAs. Those CAs in particular have been renewed ...
1
vote
1answer
51 views

what harm can a malicious ca do?

If ca's act in the interests of an eavesdropper, what is the worst they cold do? I guess they can decrypt traffic not using perfect forward secrecy and impersonate the server. Is this the case?
1
vote
2answers
60 views

Public e-mail Encryption Certificate

I'm quite new to this, so don't be too hard on me. I'm currently using the CipherMail MTA to generate e-mail encryption certificates. I created an own CA and public and private keys for our contact ...
2
votes
3answers
55 views

Are Extended Validation certificates any more secure than regular ones?

Or are they just an attempt to get you to pay more money to a CA because it tells your browser to show the address bar in green with your organization's name? Also, what are the technical details ...
0
votes
1answer
32 views

Is it possible to create a SMIME only PKI that *can't* be used for SSL?

Assume I have a Root CA that I want to share with hostile untrusted 3rd parties. Then constrain this root using specific EKUs at the root. OID=1.3.6.1.5.5.7.3.4 ; Secure Email Next, ...
1
vote
2answers
60 views

Authentication through digital certificates plus signature

While studying X.509 certificates, I've found that authentication is safer if I associate/combine one or more certificates with each signed message (certificate + signed message). The receiver of ...
2
votes
3answers
78 views

How are public key certificates updated securely?

Let's say I get a new computer that's never been connected to the internet before. The first time I connect it to the internet, is it susceptible to a mitm attack while downloading its public key ...
2
votes
2answers
81 views

Certificate authority structure - best practices

I'm working for a company that sells software products to customers some of which do not have the resources and/or know-how to build and maintain their own CA (used for the SSL communication of our ...
0
votes
4answers
105 views

Can a certification authority sign another CA's certs?

Disclaimer: I have low knowledge of X.509 and PKI, so I would appreciate an answer that is not entirely technical, i.e. by using real-life example scenarios.) I was searching for information ...
2
votes
2answers
176 views

What happens if the CA has knowledge of private keys?

In a classic PKI scenario, the certificate authority receives signing requests generated by an end-user which owns the keychain, and thus has his private key secret. Consider a scenario in which the ...
0
votes
1answer
163 views

How to become an internationally recognized certificate authority (CA)?

What's the procedure a certificate authority (CA) must follow to get internationally recognized, like Verisign or GlobalSign?
0
votes
1answer
130 views

Trusted Certificate Authorities - how do they work?

microsoft.com for example can use a Verisign Certificate for their domain. What are the chances that an attacker could ask verisign for a m1crosoft.com domain and get approved? It is very simillar, ...
1
vote
1answer
40 views

In a 3 tier (or more) PKI, is it permissible that a Name Constraint only be defined on the middle tier?

I'm working with an Issuing CA that doesn't support name constraints that are defined at a higher level. Assuming that it issues certificates that are compliant with the Name Constraints that are ...
3
votes
1answer
136 views

Internal code-signing certificate on Windows

I'm looking to improve defense-in-depth on a system, primarily by closing some holes in injected DLLs. Certain applications installed on the system cause helper DLLs (e.g. shell extensions, BHOs, ...
6
votes
5answers
276 views

Why are private certificates not trusted?

When we go to websites that have generated certificates themselves you see this red screen that says do not go there!: However when it is trusted by some companies it's all good. So I have a couple ...
2
votes
1answer
506 views

Root certifcate key usage (non-self-signed end entity)

This discussion does not include self-signed end entity certificates for hosts like web servers and mail servers. OpenSSL's default configuration for a CA certificate has the following keyUsage: ...
2
votes
1answer
188 views

How can a trusted intranet certificate be issued if they are being phased out?

I've just seen this article regarding the phasing out of intranet names on SSL certificates. However, CAs such as this one claim to still issue them and it will be "Trusted by all popular browsers" ...
1
vote
4answers
148 views

search CA for someone's public key

do CAs offer service wherein an application can request someone's public key? i am trying to do this but i am unsure if it is correct (suggestions of better ways to do it will be most appreciated): ...
4
votes
1answer
371 views

Who is this strangely named Certificate Authority?

I'm researching certificate authorities, and I just have no idea what to think of the CA named x00Ax00-x00Tx00rx00ux00sx00tx00 x00Gx00ex00sx00.x00 x00fx00xFCx00rx00 ...
2
votes
1answer
99 views

What do people mean by “top-down manner” in X.509 certificates?

What do people mean by saying that X.509 certificates work in "top-down manner"? Do they say that because CAs can do cross certifications?
4
votes
3answers
205 views

Certificate Transparency

From what I read here, if the intermediate CA has been compromised, a fake cert can be issued and the privacy of the end-users could be compromised as well. In order to remediate this situation, ...
2
votes
4answers
285 views

Evil certificate authority in public-key-infrastructure

Alice goes to the certificate authority (CA) and registers her public key for signature verification. She gets a certificate for this from the CA. Bob requests Alice' public signature verification key ...
3
votes
3answers
534 views

What stops a hacker from installing it's own CA certificate?

Taking a look at this (now rather old) article about the generated rogue DigiNotar certificates, it states the following: ...Such is the case with that small company in the Netherlands, ...
0
votes
1answer
191 views

SSL (TLS v1.2) - Can i offer fallback CAs when upgrading Certificates? (Java)

I am currently developing a product that involves two network situations. At the client side, multiple computers form a P2P network (multiple locations, multiple p2p networks), and a subset of nodes ...
12
votes
5answers
2k views

Are self-signed certificates actually more secure than CA signed certificates now?

Are self-signed certificates actually more secure than CA signed certificates now? I ask this because recent leaks about the NSA spy programs and the secret FISA courts mean that the US government ...
4
votes
1answer
81 views

What is the meaning of http://uri.etsi.org/TrstSvc/eSigDir-1999-93-EC-TrustedList/SvcInfoExt/RootCA-QC from ETSI TS 102 231 V3.1.2

From Technical Spec http://uri.etsi.org/TrstSvc/eSigDir-1999-93-EC-TrustedList/SvcInfoExt/RootCA-QC a Root Certification Authority from which a certification path can be established down to ...
3
votes
2answers
427 views

Possible to use a YubiKey in HSM mode to secure a Windows CA infrastructure?

I'm looking for a low-cost Hardware Security module, and discovered that YubiKey has a HSM mode. I'm not entirely clear if this HSM mode is what I'm thinking, but I'd like to use it as the offline ...
5
votes
2answers
628 views

Root SSL certificates and browser support

I have given three certs to be install on nginx AddTrustExternalCARoot.crt PositiveSSLCA2.crt www_example_com.crt So I concat them into a chained cert cat www_example_com.crt PositiveSSLCA2.crt ...
3
votes
4answers
222 views

Trust among the root-CAs

The system of CAs with the root-CAs and their subordinate CAs are IMHO in principle akin to the system of banks with their main sites and subsidiries. In the case of banks, a customer of a bank ...
3
votes
1answer
152 views

Design of system based on HTTPS, Client Certificates and custom CA

I have the following system: 2 application servers. At the beginning is installed the first server and later is installed the second one. A client access from a browser to both servers Application ...
7
votes
5answers
3k views

A standard way to manually add a digital signature to a pdf file?

I've created a few certificates to use myself, but I find myself stumped when it comes to creating a certificate which contains a digital signature. First, how would I go about creating a standard ...
1
vote
1answer
187 views

are organizations that receive certificates considered “end entities” in a PKI?

I am trying to understand the term end-entity. Does this term just mean anybody that plays a role in a PKI system that is not a CA? So if I request a certificate from A who is a CRL issuer for ...
11
votes
2answers
922 views

What does having an internal two-tier PKI protect against?

There are a lot of Best Practice documents that recommend having an offline Root CA and an Enterprise Subordinate CA that is signed by the root, for an internal Microsoft AD Certificate Services ...
4
votes
3answers
509 views

Why are SSL certificates valid only from a certain date?

Each SSL certificate is valid starting from a specific date and up to the expiration date. What's the point in that "valid from" date? Why do we want a certificate to only be valid after a specific ...
1
vote
1answer
170 views

How to have Thunderbird include a root certificate?

An eMail signed via S/MIME also contains the X.509 certificate chain containing the public key in order to directly verify the signature (assuming its issuing CA is deemed trustworthy). The chain does ...
3
votes
1answer
336 views

Internal CA for Digital Signature Solution - PKI Based

I'm trying to set up a digital signature solution which would work with a internal PKI. We have considered Microsoft Certificate Services, but we don't want to rule out any other option to set up a ...
50
votes
10answers
7k views

Why do we not trust an SSL certificate that expired recently?

Every SSL certificate has an expiration date. Now suppose some site's certificate expired an hour ago or a day ago. All the software by default will either just refuse to connect to the site or issue ...
4
votes
4answers
2k views

Is it possible to create a self signed certificate authority?

Would it be possible to create a legitimate certificate with the CA bit set? I dont have a usecase associated with this, I'm merely curious. To explain my question : Suppose I sign a public ...
1
vote
1answer
724 views

How does a developer interact with Microsoft Certificate *Web Services*

Microsoft Certificate Web Services is a HTTPS web service (WS-Trust) that has no Kerberos dependency and can be used on a variety of devices. This is new in Windows 2008 and is separate from the ...
5
votes
1answer
3k views

What damage could be done if a malicious certificate had an identical “Subject Key Identifier”?

I'm looking at the the Subject Key Identifier attribute of a CA certificate and am trying to understand the role it plays in validation and infer how validating client software could get it wrong. ...
3
votes
1answer
111 views

Is it a good idea to generate certificate-specific CRLs? What is this technique called?

Suppose I create 3 certificates with the following CRLs Cert1 http://crl.server.com/batch1/root1.crl Cert2 http://crl.server.com/batch2/root2.crl Cert3 ...