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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2
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2answers
54 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
votes
2answers
112 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 ...
11
votes
3answers
185 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
votes
3answers
199 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 ...
15
votes
2answers
262 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 ...
3
votes
0answers
41 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
votes
1answer
129 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
votes
2answers
92 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 ...
1
vote
2answers
62 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 ...
1
vote
0answers
26 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
vote
2answers
59 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 ...
1
vote
2answers
97 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
votes
1answer
62 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 ...
8
votes
2answers
589 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
votes
2answers
100 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 ...
-3
votes
2answers
73 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 ...
1
vote
2answers
93 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
votes
1answer
76 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
votes
2answers
54 views

Analyzing whether browser certificates have been compromised

How can I know that my installed certificates (in Firefox), are (still) reliable?
0
votes
2answers
125 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
vote
1answer
65 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
vote
3answers
87 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
80 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 ...
2
votes
1answer
54 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 ...
1
vote
1answer
21 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
85 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
vote
2answers
56 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
votes
2answers
59 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
vote
1answer
43 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
votes
1answer
32 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
vote
2answers
61 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 ...
5
votes
1answer
66 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
vote
1answer
78 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
60 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
46 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 ...
2
votes
2answers
71 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
votes
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
votes
4answers
4k 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
votes
0answers
42 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
vote
1answer
30 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
98 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
vote
2answers
50 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 ...
2
votes
0answers
34 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
votes
3answers
129 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
votes
1answer
191 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 ...
3
votes
1answer
184 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 ...
8
votes
1answer
121 views

How can I protect myself against software installing insecure root certificates?

With the recent news that Dell installed a root certificate with a publicly accessible private key on their notebooks, I'm wondering how I can protect myself against this kind of incompetence. Of ...
12
votes
1answer
288 views

Alternatives to HTML's deprecated <keygen> for client certs?

The keygen tag is used to make browsers generate private keys and POST the resulting CSR to the server, which can then issue a certificate. It's now been deprecated, for rather stupid reasons but ...
16
votes
4answers
2k views

Broken SSL on every website [duplicate]

One of my friends called me saying every website anyone in her family goes to has untrusted SSL certificates. From any computer in her house, HTTPS is broken and Firefox or Chrome asks to add an ...