Certificate Revocation is a process through which we make sure that those certificates that are not considered valid are not used by relying parties.

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142 views

What considerations should apply for self service Renewing, Revoking, or Unrevoking a certificate?

I need to design a self service portal for renewing, revoking, and unrevoking a certificate and have come up with the following rules*: Renewal Certificates have a short term validity and need to ...
2
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2answers
167 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 ...
3
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3answers
2k 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 (...
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5answers
2k views

Why are certificates limited in time?

If a certificate has a limited duration of, say 5 years, but it gets somehow compromised after 2 years, waiting the 3 remaining years for it to get invalid is not a real solution to the breach problem....
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2answers
241 views

A doubt in certificate chain validation and revocation checking

So when i do a tls handshake with the server, it responds with a cert chain which the browser verifies and which ends at a trusted root CA. In this the browser checks if the cert presented by the ...
2
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1answer
117 views

How does checking CRLs make sites less safe?

With the frantic certificate upheaval resulting from the Heartbleed fiasco [drink!], there has been lots of talk regarding certificate revocation, and in particular the policy of certificate ...
4
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3answers
642 views

How are CRLsets more secure?

Google Chrome doesn't do typical CRL/OSCP checks, instead it depends on CRLsets. In simple terms, Google scoops up the CRLs from most CAs, trims them down and delivers the CRLset to the browser via ...
4
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2answers
3k views

How to configure Browser to detect revoked certificates?

In the context of the Heartbleed bug I would like to make sure that I can detect if someone tries to do a MITM attack with a stolen certificate, which since has been revoked. The problem is that ...
8
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1answer
495 views

How can I verify if a website revoked its old SSL certificate keys? [duplicate]

Through reading from multiple sources and watching Security Now's How the Heartbleeds, I have come to the understanding that the following procedure is recommended to be safe from the Heartbleed ...
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2answers
1k views

SSL cert minimize downtime key rotation strategy

As you already know, due to the heartbleed bug, we need to perform re-keying on our web servers (>10), before I do that, I want to check if my proposed strategy is a proper way or not a. Generate a ...
3
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1answer
437 views

How to handle CRLs correctly in long-term electronic signatures?

What is a recommended way of handling CRLs in long-term electronic signatures (specifically the CAdES-A)? The problem I see is in that CRLs are not protected against modification (they are plain text,...
0
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1answer
125 views

Good reason to continue using fraudulent certificate?

A relative of mine used a favorites link to login to yahoo. The favorite link is https://de.mg40.mail.yahoo.com/neo/launch? However, this link uses a fraudulent certificate. Visiting the Yahoo ...
2
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1answer
103 views

Is a PGP revocation certificate sensitive?

In relation to an openpgp key on a smartcard: Besides revoking the key, is there anything else it can be (ab)used for? Can I just ensure it's reliably stored but not worry about it's confidentiality?
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0answers
34 views

Specify port for cRLDistributionPoint?

cRLDistributionPoints is OID 2.5.29.31. Here's what one looks like under Gutmann's dumpasn1: SEQUENCE { OBJECT IDENTIFIER cRLDistributionPoints (2 5 29 31) OCTET STRING, encapsulates { ...
0
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1answer
226 views

Should all Server Certificates from one CA have the same CRL

I am setting up my own PKI, and I came across a question to which I couldn't find an answer. I want to specify CRLDistributionPoints in my server certificates but I am curious whether to use the same ...
3
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1answer
125 views

In theory, can x509 certificates use Accumulator-based revocation schemes? How do these schemes work?

On page 3 of this U-Prove document regarding toke revocation, the author says the benefit of Accumulator-based revocation schemes is A cryptographic accumulator allows the aggregation of a large ...
5
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3answers
4k views

Revoke a certificate without index.txt

I generate self-signed client certificates for a little Apache server hosted under my stairs. The script below was hacked together for this purpose - note it uses the 'mini-CA' x509 method, therefore ...
8
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1answer
943 views

Force a subordinate CA cert to be signed to include a the CRL distribution point extension?

How can I attach a crlDistributionPoints parameter when signing a CSR I've generated as follows: openssl req -new -key /root/ca/private/private.key -out /root/public.csr I usually sign with: ...
5
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3answers
2k views

Why do we allow SSL certificates to be replaced before their expiry date, without revokation of others?

Imagine a situation where a rogue CA creates a certificate for your site. Since the user's browser trusts the CA, it will accept the certificate without any fuss. However, the site's real certificate ...
5
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1answer
5k views

AIA/CRL locations for Offline Root

I've read the answer to the following "Checklist on building an Offline Root & Intermediate Certificate Authority (CA)" and I have one questions based on the system I am trying building It's an ...
6
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3answers
670 views

Why does OpenSSL need the private key to revoke a certificate?

openssl ca -revoke signed/0A.pem -config caconfig.cnf What does this do which requires the CA's private key? Does it do anything except updating index.txt?
10
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1answer
571 views

Why can the validity of an SSL certificate exceed the registration period of a domain?

I can understand why one might desire to purchase a certificate for multiple years but I am left wondering why it appears to be possible to obtain a valid certificate for a domain that may have come ...
14
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3answers
283 views

Domain name expiration and TLS

If I purchase a domain name that has expired, do I have any assurance that the previous owner does not have a valid HTTPS certificate for the site? In other words, do CAs check domain name expiration ...
2
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1answer
3k views

How does an offline CA revoke certificates?

If an RSA private key of a root CA is stored offline, how does it revoke certificates it signs? From looking at OpenSSL config the default_crl_days option seems to indicate that a CRL must be ...
4
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1answer
174 views

User Groups (Circles) Inside a Web of Trust

Assume I have a universe of U users. Every user has his private key. I want to build user groups by adding a company sub key to his key set. Now users can sign his company sub key with there company ...
2
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2answers
1k views

distribution mechanisms for CRLs

From the X.509 RFC: DistributionPoint ::= SEQUENCE { distributionPoint [0] DistributionPointName OPTIONAL, reasons [1] ReasonFlags OPTIONAL, cRLIssuer ...
5
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3answers
420 views

What is a reasonable expiry for user authentication certificates?

This question is about a nearly decentralized P2P system with a centralized certificate authority where users can authenticate and receive a certificate on their public key and then can authenticate ...
2
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1answer
5k views

What Enhanced Key Usages are required for PKI infrastructure tasks? (OIDs for OSPF and CRL signing, etc)

I'm building a constrained PKI that specifies EKUs for the the entire hierarchy and want to document the OIDs required for PKI tree maintenance tasks. I understand that clients may not validate the ...
0
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1answer
542 views

Does S/MIME provide means to propagate a certificate's revocation?

Can a revocation certificate for an old X.509 certificate be attached to an email in addition to a replacement certificate in such a way that the client user does not have to manually intervene? Or ...
3
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2answers
5k views

Ssl certificate rekey or revoke

I want to be sure to understand well the situation where SSL certificate is compromised. If I ask for a rekey, I suppose the old certificate will remain valid. The future communications with the new ...
2
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3answers
609 views

Are intermediate signing certs the only secure+practical way to manage OpenVPN client certs?

My organization needs to issue (and revoke) OpenVPN client certificates for people working remotely. Our system is based on a standard OpenSSL CA setup and the easy-rsa tools, and the whole directory ...
3
votes
1answer
2k views

What should a CRL file name look like when “new” and “delta” CRLs are generated?

I suspect my Windows 20012 Certificate Server CRL revocation configuration is incorrect every time I generate a new CRL or a new Delta, only a maximum of 3 files are generated. When I created the ...
3
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1answer
240 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 http://crl.server.com/batch3/root3....
6
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2answers
7k views

Is an AIA or CRL useful / required at the Root CA if that Root is used to cross certify another PKI?

Suppose I have several independent PKIs that are used Two internal PKIs: One with SHA1 support the other with Suite B algorithms. A partner who I trust and have a policy map with. Since both my ...
1
vote
1answer
565 views

When distributing a CRL over HTTP, what is the optimal refresh time? What logic affects this decision?

When distributing a CRL over HTTP, what is the optimal cache and max age settings (etc) for this distribution mechanism? Related information on a different answer Consider using HTTP instead ...
12
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4answers
2k 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 ...
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 ...
2
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1answer
376 views

Signature and Timestamp for Long Term Document Archival Question

I have a PDF document intended for long-term (many years, maybe decades) archival which I would like to digitally sign with my personal certificate to ensure its integrity. As far as I understand, I ...
2
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2answers
105 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) ...