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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14
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3answers
281 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 ...
12
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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 ...
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 ...
12
votes
2answers
1k views

Is publishing CRLs over HTTP a potential vulnerability?

I noticed that at least one major CA (Comodo) publishes their CRL over HTTP rather than HTTPS. This seems to me to be somewhat of a vulnerability, as an attacker could hijack the HTTP connection that ...
12
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1answer
740 views

Why isn't there a certificate revocation request standard?

Say I am building a Certificate Authority software and I want to automate certificate revocation as much as possible. I know it will not be possible in some cases, like if the building where the ...
12
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2answers
2k views

When does iOS check validity of enterprise certificates?

Here is an article that should give a little more context (and see my comment on it, same username, for additional info). iOS developers are able to distribute apps outside of the App Store using an ...
10
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1answer
566 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 ...
10
votes
1answer
854 views

Should I use a Certificate Revocation List?

I've been trying to provide security to my API. I will issue certificates to my clients to access my API through a TLS channel. So it'll be a SSL-Client Authentication. I'm wondering, should I use ...
10
votes
1answer
225 views

Did D-Link's certificate revocation really only invalidate 1 day (of a six months long exposure)?

I'm trying to wrap my head around the OCSP revocationTime for D-Link's certificate. I recently answered another question and ended up drafting a timeline. That timeline is basically this: Jul 5 ...
8
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1answer
2k views

Has the leaked D-Link windows signing key been revoked?

Recently news broke as to D-Link mistakenly publishing a private code-signing key as part of an open source framework. The D-Link key was leaked in late February, and expired on September 3, it ...
8
votes
2answers
86 views

What does “revoking” a key actually do?

I am currently encrypting some personal information using gpg (gpgdir actually). I have a copy of my private key printed onto a sheet of paper in the form of a data matrix lest I lose the digital copy ...
8
votes
1answer
477 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 ...
8
votes
1answer
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 ...
8
votes
1answer
917 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: ...
7
votes
2answers
2k views

Website Certificate Revocation check - Big deal? [duplicate]

As I was about to make payment for my flight ticket, I noticed something strange with the British Airways website's SSL cert. My browser (Google Chrome) was unable to check whether the certificate has ...
6
votes
3answers
644 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?
6
votes
2answers
528 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 ...
6
votes
3answers
5k views

Why are Certificate Revocation List periodically renewed?

While studying a security course I have been asked this very question: Why are CRL periodically renewed, even if there are no new revoked certificates to add to the list? Honestly I can't find the ...
6
votes
2answers
6k 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 ...
6
votes
1answer
102 views

How to check which certificate is being checked for revocation?

I have a .net desktop application without a certificate on a network not connected to the Internet When I start it, there is a call to crl.microsoft.com that times out and slows down the application. ...
5
votes
3answers
823 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, ...
5
votes
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 ...
5
votes
3answers
1k 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
votes
1answer
77 views

Why are short-lived certificates so rare?

Let's encrypt recently left beta and limits the maximal life-time of certificates to 90 days and recommends 60 days. Now whenever I start talking about the issues of certificate revocation (e.g. OCSP ...
5
votes
2answers
127 views

Why do so many browsers show sites with revoked certificates?

Everyone seems to agree that it is REALLY important to protect private keys so the encrypted Internet can remain just that (see for example at How do certification authorities store their private root ...
5
votes
3answers
414 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 ...
5
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2answers
2k views

Is there any malicious reason to block CRLs?

I've noticed that in order to 'illegally' crack certain applications, it is necessary to patch the host file to stop communication with the activation servers. I've found that with several ...
5
votes
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 ...
4
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2answers
37 views

What is the difference between Digital certification revocation and retiring?

Certificate management tools use options called revocation and retiring digital certificates.Can someone explain what is the difference between both?
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 ...
4
votes
1answer
172 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 ...
4
votes
1answer
44 views

Mail Signing Certificate – What are the impacts when revocated?

Suppose I open a signed mail on 1st January 2000, signature is OK. What about this two cases : 1) If next CRL is to be published one week later, I found it strange that it is “probably” valid until ...
4
votes
3answers
619 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 ...
3
votes
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 ...
3
votes
2answers
4k 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 ...
3
votes
1answer
236 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 ...
3
votes
1answer
190 views

How to trust a CA to sign a CRL but not a cert?

In my application, there are many parties that are trusted to revoke a cert (ie by signing a CRL), but are not trusted to sign (new) certs. How do I mark a CA to be trusted only for CRLs, and not for ...
3
votes
2answers
387 views

S/MIME certificate expired and renewed, do my correspondents have to do anything?

My PKI certificate (Digital ID for email from Symantec, issuer is "VeriSign Client External Certification Authority - G3") expired after 1 year and so I have renewed it. Do the people I correspond ...
3
votes
1answer
131 views

Understanding how does certificate validation work

I'm using Wireshark for better understanding how is a SSL connection established. I captured the traffic of visiting three pages: reddit, facebook and this one. All HTTPS of course. Reddit: after the ...
3
votes
1answer
422 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 ...
3
votes
3answers
269 views

The best way to change my pgp key

I would like to change my pgp key because I have the same one 2 years ago. But, I want to warn my freinds that the owner of the old key and the owner of the new one is the same person (me). hwat is ...
3
votes
2answers
250 views

SSL certificate renewal and downtime due to revocation

We are in the process of renewing an SSL certificate, mainly for the forced use of SHA256. It is my understanding that a new Certificate Signing Request (CSR) has to be issued for the same host name, ...
3
votes
1answer
19 views

Does it matter what version of GnuPG I use to create revocation certificates?

Today I am about to create a bunch of revocation certificates for all of my emails. Why? Because it already happened to me in the past, that I lost my private key, or my computer was compromised. It ...
3
votes
1answer
20 views

Do I need separate revocation certificates for each email address associated with a key?

I just created my first OpenPGP key with GnuPG + Thunderbird + Enigmail. The key is used for two email addresses. Now I created a revocation certificate. There is only on of the email addresses ...
3
votes
3answers
99 views

Compromised Issuing CA

I'm configuring a PKI infrastructure with an offline root CA and several issuing CAs. Among other topics, I'm struggling to decide how the revokation of an Issuing CA certificate works. My Root CA ...
3
votes
2answers
93 views

Cetificate Pinning. How do we handle the situation where a website is visited for the first time?

What I essentially mean to ask is, how is the scenario where a user who visits a website for the first time (the certificate for the website is not pinned in the browser) handled ? Additionally how is ...
3
votes
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 ...
3
votes
1answer
50 views

How is validating an SSL certificate against a CRL not inefficient?

My understanding is that CRL is a list from a CA that says what certificates not to trust. Browsers will regularly download these lists from their trusted CAs and check the certificate of requested ...
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 ...
2
votes
2answers
142 views

Should expired compromised certificates be taken care of if the time is always correct?

I am trying to set up a CA for my company, and issuing every employee a digital certificate and a private key. I am worrying about revocation and expiration. In my case, the root certificate of CA is ...