A piece of data used in public key cryptography that contains identifying information (i.e. email address or web address), a hash of a public key, and a digital signature that authenticates the data in the certificate.

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136 views

Why/when would a CA make a generated public key available to the public at large?

I'm confused about this section in my CEH security exam training material: A CA is able to perform a number of roles in addition to the validation process outlined here. Some actions that a CA is ...
5
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1answer
114 views

Securely build a list of trusted CAs

Some distributions of the cURL bundle include a utility mk-ca-bundle.pl which compiles a ca-bundle.crt from Mozilla's root certificate store for use as a list of trusted authorities. The script prints ...
2
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1answer
112 views

How does Windows certificate manager verify a file's certificate, if the root certificate is not in the store?

I'm working on a project which requires certificate verification for executable files. I have created my own trusted root certificate store, and used openssl to perform verification. However, when I ...
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0answers
25 views

Is there any extra validation that Firefox perform to certificates serial number

I open a secured site in my computer. for my reasons, I created new certificate every 15 minutes. I noticed that, sometimes, Firefox "doesn't like" my certificate. after little investigation, I ...
2
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2answers
66 views

Why not to use the same subordinate issuer CA for generating certificates that will be used for different things?

Microsoft has recommended my organization to use different subordinate issuer CAs in order to issue certificates that will be used for different things. For example, they recommend to use a CA for ...
5
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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 ...
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3answers
199 views

Why is Firefox shipped with expired root certificates?

What's the purpose of shipping Firefox with expired root certs? I checked and there are two expired certs listed. In fact the company's website for the first expired cert (A-Trust) states that the ...
6
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3answers
275 views

Why should my certificate signing request be signed by my private key?

Why should my certificate signing request be signed by my private key? Even if I obtain a bogus certificate out of someone else's public key, that is going to be useless, since in SSL the ...
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2answers
557 views

How much of a problem is it that Windows “hides” some of the trusted root CA certs?

Based on information on this page, Windows actually trusts many more root CA certificates than what are displayed when a user launches certmgr.msc and navigates to Trusted Root Certification ...
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0answers
50 views

Certificate and Path validation for S/MIME

I am working on a S/MIME client development and was wondering if there is a list of certificate and path validation checks that a client needs to perform while validating an email signature. My ...
6
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1answer
193 views

Client identification using client certificates

I have the following scenario: Several independent embedded servers (Linux/ARM/lighttpd) Several independent controlling devices (win32/iOS/Android) Each server should have at least one controlling ...
5
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2answers
184 views

How do I produce a CA signed public key?

I have a need to have somebody else encrypt secret data with my public key that I can then decrypt with my private key. I have produced an RSA private/public key pair with OpenSSL gave them the public ...
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2answers
113 views

Application that uses USB token to assign user on a server

I have the following situation: One user with a USB token certificate access a site and log-in using this certificate, the logging process ask for the USB token password; When the user is logged he ...
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0answers
27 views

Can there be two certificates with a same serial number in the world? [duplicate]

Recently I came across this odd question. I hope, Serial number is unique across certificates signed by a particular CA. So is there any chance that two different CAs sign two different certificates ...
1
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2answers
64 views

Do secure ciphers break multi-domain certificates?

In the past days, I was halfway successful with securing my websites. So far, I have achieved the following: Get a certificate from letsencrypt.org, securing the domains example1.com, example2.com ...
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2answers
115 views

What server software uses .der?

So apps linked against openssl uses PEM, and Windows generally uses PKCS12, but I haven't seem much .DER in the wild - what server software uses DER?
0
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1answer
74 views

Why does not appear the public key from certificate?

I'm creating a certificate in LAMP, the public key is: Public Key: 30 81 89 02 81 81 00 CC CB 64 54 C2 FA A3 7A 81 36 5F 1B D5 10 81 75 B7 42 02 31 83 B1 D5 5A 76 72 6A 77 BE 62 69 16 AB EB 39 66 B5 ...
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2answers
599 views

How do user receive server's certificate?

Let's imagine our user's computer wants to talk to some server for the first time in history via https. The computer sends a hello message, the server sends his public key and the certificate, ...
3
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2answers
114 views

Using Self sign certificate in internet

Basically the purpose of SSL cert is for trusting each other. If I have an application that only a few clients I know can use, is generating self sign certs enough? Or do I really need to sign with a ...
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2answers
174 views

Client certificate vs HMAC

My team is working on web API project for one customer which will call this API. Now we are thinking about authentication. We've stopped on two options HMAC and client certificates HMAC: pros - no ...
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2answers
104 views

Verification of client certificates

I've read a lot of articles about client certificates. Please correct me if I'm wrong: client certificates are issued using CA CA could be created by myself (self-signed) or bought client ...
3
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1answer
113 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 ...
0
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2answers
59 views

Analyzing whether browser certificates have been compromised

How can I know that my installed certificates (in Firefox), are (still) reliable?
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2answers
140 views

Why can you not trust a certificate directly?

If you want to set up a service that is signed using some Certificate Authority system (SSL/TLS, certain configurations of IKE, etc), if you want to use a self-signed certificate (e.g., for testing), ...
1
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1answer
92 views

Are fields of a root CA certificate checked?

During SSL server validation, it seems that the only fields of X509 certificates found in trust stores that are actually used are the "Common Name" and the "Public Key". I'm not talking about any ...
1
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3answers
92 views

HTTPS client “pairing”

I've been redirected here from SuperUser, I hope the question is appropriate. I need to restrict usage of a certain site to a limited number of customers. More than that, actually: I would like to ...
4
votes
1answer
134 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 ...
3
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1answer
130 views

When can I commit an OpenSSL Certificate (.pem) to source control?

That is to say, in what cases does it make sense to commit .cer files, or a stack of .cer files in a .pem, to internal source control like SVN or Git? If it's just a list of signed public keys, I ...
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1answer
45 views

Prevent credential roaming for certain accounts/certificates?

I want to use credential roaming in Windows 7, 8 and 10 for EFS certificates, so users can access their encrypted files from any computer they login to. However, some of these users will also have ...
2
votes
1answer
144 views

Why do Browsers warn about self-signed certificates but not about plain HTTP (which is not even encrypted)? [duplicate]

Let's keep it short: On HTTP everyone can listen easily. MITM attacks are no problem. On HTTPS (self-signed) everything is at least encrypted, it's much harder to MITM-attack and only private key ...
1
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2answers
76 views

Find private key from private certificate

I have a private certificate from my email server in order to sign emails. At Section "Your S/MIME Personal Certificate" I can view my: private certificate public certificate My public certificate ...
0
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2answers
71 views

Why handshake is not initiated for google webserver?? Is there any client side validation before handshake is initiated?

I'm using burp suite as proxy and configured my browser to it. I'm able to intercept SSL connection traffic of only some web applications using self-signed certificate issued by burp by adding ...
13
votes
4answers
1k views

How do certificate issuers become trusted?

From what I understand, the certificate scheme that TLS/SSL relies on works because your computer has trust for major CA issuers built into it. That is, your OS is installed with certificates for ...
1
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1answer
93 views

How to read certificate chains in OpenSSL

I'm trying to understand how to read the output of OpenSSL commands. Currently, I am trying to understand how Certificate Chains work. When I give the command (using a standard ca bundle) openssl ...
0
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1answer
36 views

For X.509 Certificates where is the actual digital signature?

When you open up the certificate information from your browser and go to the details tab there is a bunch of information for various certificate fields. I am wondering which field contains the actual ...
1
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2answers
84 views

wordpress server certificate does not match url

When visiting a WordPress blog using HTTPS Chrome gives me a warning that the domain on the certificate (*.wordpress.com) does not match the URL (someguysblog.com). This seems to be a known issue. So ...
6
votes
1answer
74 views

Is there any benefit in having CNNIC certificates installed, if you're not in China?

All modern browsers/OS come with root certificates from the China Internet Network Information Center. AFAIK these certificates are required for computers sitting behind the Great Firewall to function ...
1
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1answer
93 views

How to determine which Browser Certs to reenable on a per-case basis?

Considering that there is no way to actually see which certs that I use in my regularly-visited websites, I've decided to disable all certs and re-enable them on a case by case basis. This is for the ...
0
votes
1answer
66 views

What is the purpose of a man in the middle certificate?

So I'm at work today and I'm having all kinds of issues getting into secure sites that I need to do my job. So I go to portal.azure.com and I find out that the certificate for the site isn't issued by ...
3
votes
2answers
57 views

Rerouting domains and the need for multiple SSL certificates

If a domain URL is registered with a .com (www.example.com) and we would like to re-route to this domain from a second domain name with a .com.tr (www.example.com.tr), is this possible? The .com ...
3
votes
2answers
192 views

What's the difference between Comodo Premium and Positive SSL certificates [duplicate]

I'm just about to buy a SSL certificate from Comodo, I've doing a research in many CAs, many of them have this kinda premium certificate, and another like positiveSSL, rapidSSL, and instantSSL. The ...
42
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7answers
5k views

Is there any legitimate reason to install yourself as a root CA?

Follow up from comments on another question. Is there any reason as to why you might install yourself as a root CA on your own network? The only reason I can think of is forcing computers in the ...
30
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4answers
5k views

Corporate computers have own corporation's cert as trusted CA; should I consider all traffic compromised?

By my admittedly limited understanding of how HTTPS/TLS works, the end user (me) initiates a connection with a remote server which signs every one of its messages with a public key. This public key ...
0
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0answers
48 views

deceptive digital signature?

I am new to cyphering and I try to understand this case : my government sends me so-called "digitally signed" PDFs, as you can see below (text only, after "Thanks"). Although there is a certificate ...
1
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1answer
56 views

SSL/TLS certificates that only certain users can use to talk to my server

are there something like SSL/TLS certificates or other equivalents which could allow only certain trusted users (from the internet) who have my server credentials in their browser to access my web ...
2
votes
1answer
108 views

Should we trust online banks with our credit card information?

I'm thinking of buying a product for someone using the steam platform. Being in Germany, the best (least expensive) option would be to use a local bank. Logging in, choosing a product and checking out ...
1
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2answers
222 views

Generate CSR and private key with password with OpenSSL

I am using the following command in order to generate a CSR together with a private key by using OpenSSL: openssl req -new -subj "/CN=sample.myhost.com" -out newcsr.csr -nodes -sha512 -newkey rsa:...
2
votes
0answers
52 views

Windows IIS Event/Security Log ID of Private Key deletion of corresponding TLS certificate?

I'm in the middle of writing an MS Active Directory Certificate Services Key Management Lifecycle document for my organization. The primary purpose certificates will serve for this organization is to ...
2
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3answers
138 views

Why include a private key in a root certificate?

In the recent Dell root certificate issue (see https://threatpost.com/dell-computers-ship-with-root-cert-private-key/115455/), the private key was included with the certificate. This is baffling to ...
2
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1answer
1k views

OpenSSL check if a SSL certificate is SHA-1 or SHA256 signed

How do I check if an OpenSSL certificate issued to a site is SHA-1 or SHA-256? I have a quite a lot of intranet sites using OpenSSL certificates and I am a bit confused as when I check the certificate ...