A Certificate Authority is the collection of hardware, software, and people responsible for issuing certificates in a hierarchical PKI. CAs may be public, as in SSL / TLS and government IDs, or private, as in corporate infrastructures. The primary responsibility of a public CA is to verify the ...

learn more… | top users | synonyms (1)

4
votes
1answer
125 views

Issuing and managing large numbers of certificates for client authentication

I am developing an Internet of Things product and plan to use client certificate authentication, issuing each "thing" its own certificate on the production line so that it may authenticate with a ...
4
votes
2answers
82 views

Is it a good practice to use certificates as a mean of client identification in a cloud environment

My software system is running a cloud infrastructure where having Linux machines VPN into OpenVPN gateway is a setup requirement. Also, there may be cases when software on the aforementioned Linux ...
4
votes
2answers
214 views

Why did browsers deprecate 1024-bit RSA, but retain SHA-1?

I was reading Mozilla's security blog Phasing out Certificates with 1024-bit RSA Keys. Effectively, some browsers are deprecating 1024-bit RSA for CAs and Subordinate CAs because the certificate must ...
4
votes
1answer
693 views

Self-signing client certificates and distributing them, is the following a sound procedure?

I have a case at hand as follows: There is a number of clients in Internet (i.e. untrusted channel), initially in hundreds but growing in numbers. There is a server doing processing related to these ...
4
votes
1answer
994 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" ...
4
votes
1answer
255 views

Remove CA from trusted CAs list while trusting it older certifications

Lets say that some certificate authority changed her security policy and we don't trust her new certifications. Is there any convenient way for an organization to remove this certificate authority ...
4
votes
2answers
141 views

Using SSL Certification in Multiple Locations

I have some issues with respect to using SSL Certificates. I have a website hosted in UK and I also have an organisation in South Africa hosting my company application online for web access. The ...
4
votes
1answer
1k views

Sites are signed with an incorrect VeriSign Class 3 G5 CA

Previously today, I encountered a SSL error trying to access twitter.com in Chrome. Investigating the issue, I encountered the same error accessing discussions.apple.com. Most other HTTPS sites were ...
4
votes
1answer
407 views

Secure Connection between two mobile (Android and/or iOS) devices

I've a Device A which will communicate with multiple devices on a network (BLE and/or NFC). All the devices will be handled a Token upon authentication which somehow needs to be transferred over to ...
4
votes
0answers
134 views

Windows Certificate Services: Is it possible to enroll a SmartCard certificate AND have key archival?

I'm using ACOS5-64 Client Kit, I want to enroll for a certificate with key archival. I tried to do so by duplicating the SmartCard template and checked Archive subject's encryption private key option ...
4
votes
2answers
185 views

Is using a self signed certificate safer than a free ssl certificate? [duplicate]

I have a personal website/email server, basically for my own self learning use. I am using CACert (http://www.cacert.org/) for my SSL certificate as advised in a tutorial. I have no clue about ...
4
votes
2answers
4k views

Windows Firewall Connection Security with Certificate

I've been fiddling with the Windows firewall configuration of some computers within a VMWare based LAN (no domain). To aid in my testing and debugging, I created a small, self-hosted console ...
4
votes
1answer
128 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
6answers
6k views

How can I know that the CA certificates in my computer have not been spoofed?

As far as I know, the browser contains the certificates of several CA. When I access http://gmail.com, the site says it is Gmail, it exposes a certificate signed by one of the CA I have in my ...
3
votes
7answers
1k views

Which forensic techniques should I use to identify intrusion or monitoring of my computer or cellphone

If I suspect my computer or cellphone is being monitored by an unknown attacker, what tools or techniques could I use to detect or identify such monitoring?
3
votes
4answers
2k views

Does http support encryption without https (like STARTTLS)?

Does http support encryption without https, akin to STARTTLS in smtp? This may sound like a stupid question, but just think about it. Banks require strong encryption, and cannot do business without ...
3
votes
4answers
264 views

Why isn't there a Global Root for SSL?

I was just wondering why there is a file on your computer implementing the trusted root CA's instead of something similar to DNS where there is a file on root servers that computers check against to ...
3
votes
3answers
1k 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, ...
3
votes
3answers
326 views

Do on-demand SSL certificates exist?

A few days ago, I visited an SSL protected website. Since Safari complained about the SSL-certificate, I did a short inspection: The certificate was issued by GoDaddy in just the minute I ...
3
votes
2answers
252 views

Is it possible for my employer to replace the root CA on my phone?

I've read about corporate MITM 'attacks' where they replace the root CA on company hardware in order to monitor traffic over SSL that takes place on their network, but is it possible for them to do ...
3
votes
1answer
2k views

Purpose of certificates signed and trusted by CA

Another newbie question but I just don't get the purpose of certificates signed and trusted by CA. We already have public/private keys, hash functions to sign/encrypt messages so why do we need ...
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
4answers
620 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
2answers
833 views

Should I customize my Root CA's thumbprint/fingerprint? (SHA1 or MD5)

My goal is to make a certificate's thumbprint "easier" to verify, and not reduce security in doing so. Given that the RSA-based Bitcoin technology has a concept called a "Vanity address" where the ...
3
votes
2answers
2k views

What to do with expired certificates as a CA?

This and this answer says that "once a certificate has expired, the CA ceases to keep track of its revocation status". I'm trying to learn how OpenSSL works as a CA. If I have a revoked expired ...
3
votes
2answers
208 views

SSL Certificate Signing by a CA

Per my understanding about SSL's, a user has to send his CSR to a CA (Verisign) to get it signed, and Verisign will send the sign X.509 certificate in return. What I don't understand is what, ...
3
votes
2answers
121 views

Can a CN-only certificate bypass a name constraint if the CA goes rogue?

I am trying to cross-certify an internal issuer certificate, adding a name constraint for our domain. However, it seems that an attacker could bypass this protection by putting the desired host name ...
3
votes
3answers
858 views

Why does the RFC 5280 dictate the CAs not to issue certificates with negative serial numbers?

I have tried to issue a certificate beginning with 8 to F but I have found it is impossible, mostly due to the RFC: The serial number MUST be a positive integer assigned by the CA to each ...
3
votes
1answer
235 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
105 views

TLS - How to know a CRL URL is not changed

If a hacker would manage to sign a certificate with a stolen (private) key of a CA and would remove or change the URL in the CRL Distribution Points extension, and later the certificate would be ...
3
votes
1answer
239 views

Check root certificates and certificate authorities on new PC

First Lenovo was caught shipping Superfish with new PCs, which included a universal self-signed certificate authority, and now Dell has been caught shipping PCs with a similar root certificate. What ...
3
votes
2answers
118 views

Is it possible to let a fake certificate appear valid by sending fake OCSP responses?

In a MITM-Attack I can exchange the server certificate by one I created on my own with tools like MITMProxy or SSLSplit. But this only works well when I have installed a fake CA cerrtificate in the ...
3
votes
1answer
187 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
140 views

Isn't this the same as using a certification authority?

Taken from Wikipedia, here is the pretext to my question: A certificate authority (CA) is an organization that stores public keys and their owners and every party in a communication trusts this ...
3
votes
2answers
5k views

Protecting against SSL Strip [duplicate]

I've read you can attack connections using tools like sslstrip, if you are on the same network. So what ensures that our SSL connections remain safe? Does it depend on the cert strength? Do you ...
3
votes
1answer
48 views

SSL negotiating too low a protocol?

I'm trying to diagnose a potential SSL/TLS problem between a Mac client and a Windows server. I have generated my own root cert and signed a cert for the server, and installed the root cert on the ...
3
votes
1answer
76 views

SSL self-signed certificates in development vs acquired cert in production?

I am a developer, I have created self-signed certificates before for my work. This time, I am involved up until going live with the whole app (usually there was someone else in charge of this). ...
3
votes
2answers
371 views

Explicitly prohibit an intermediate CA certificate on OpenSSL

How do you explicitly not trust a particular certificate (especially, CA certificate) for OpenSSL? On NSS-based applications, one can install the cert with trustarg p: prohibited (explicitly ...
3
votes
3answers
617 views

Corporate PKI - SHA1 deprecation

Here is the context. Suppose you have a corporate PKI with : AC_Root (offline in safe store - SHA1 signature) SubRootA and SubrootB (offline in safe store - SHA1 signature) SubSubRootC, SubSubRootD, ...
3
votes
2answers
416 views

Why would Comodo SSL certs have two intermediate CAs (chain length 4)?

Comodo certs such as PositiveSSL have a chain length of 4, including two intermediate CA certs. What would be the benefit to them, or to me, of this length chain instead of a chain length of 3 with a ...
3
votes
2answers
13k views

How to go about an ssl certificate renewal

I've got an ssl certificate from godaddy, and it's time to renew. I ended up with a single "keystore" file, which I give to my webserver (jetty). This is the process I went through to generate the ...
3
votes
2answers
777 views

Inspecting a TLS Certificate to determine RSA Key Usage restrictions

With regard to this answer, I have a question about Key Usage in an SSL certificate. Most SSL server certificates have a RSA key which is not restricted through a Key Usage extension, so you can ...
3
votes
1answer
80 views

Is a CA obligated to issue a certificate for a proven legitimate request?

As hinted at in Does any technology prevent a CA unilaterally revoking a certificate?, I'm a little uncomfortable with the possibility that CAs effectively licensing a website to operate (given the de ...
3
votes
1answer
75 views

Why does SSL EV certification have a range of encryption (40-128 bit)?

I would like to get SSL-EV certification for my company website. After comparing a list of providers, I am confused by their advertisements. Why do all providers say that their certifications ...
3
votes
2answers
925 views

Difference between Certificate pinning and public key pinning

I understand what pinning is. I had read about Certificate pinning and I appreciated it's use case. But today I learned pinning can be of two types - pin the certificate or pin the public key ...
3
votes
2answers
364 views

If your company/university requires you to install root certificates what protects you from man in the middle attacks?

Let's say that I'm on a university (or company) network that requires you to install a root certificate to connect to their website. Now let's say that you trust these people but not anybody else. Is ...
3
votes
3answers
769 views

Why a self-signed digital certificate (X.509) cannot be altered?

I'm not experienced in code signing but I was thinking about this: as you know, there are various tools for self-signing digital certificate generation (as makecert from Windows or OpenSSL). Now, It ...
3
votes
4answers
473 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
5k views

Certificate Chains When Importing Signed CSR Response

I'm interfacing with a secure web service, and authenticating using a client certificate. I'm confused about step #3 in the client configuration: Generate a private key into keystore Generate a CSR ...
3
votes
2answers
47 views

Question about SSL certificate and third party server

I have a system which consume web-services from a public server on Internet (but the data are not public) I have to provide credentials in Basic Auth to get the data, that is why we use SSL. The ...