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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571 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, ...
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1answer
3k views

Grey vs Green padlock in address bar - technical difference [duplicate]

What is a technical difference between "grey padlock" and "green padlock" in URL bar in browsers? As an example we can take: Green padlock: Bank of America Grey padlock: Google Search Both of ...
5
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1answer
719 views

How is an Authenticode timestamp verified?

For an Authenticode signed file to be verifiable by Windows after the original signing certificate has expired (typically 1-3 years after issue), the file also needs to have a cryptographically signed ...
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2answers
295 views

Can I buy a signing-valid certificate for internal use?

So now that I have to implement "secure transport" as defined by The Direct Project (not to mention reinventing a bunch of wheels, but that's another story for SO), I find myself staring down the ...
2
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3answers
495 views

Does HTTPS encryption work when there is invalid or there is no certificate?

When I have a website run on https and there is no certificate, there is wrong certificate or out of date like here does encryption still work or not?
0
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2answers
303 views

How to detect authenticity Of Client and Server Certificate?

How its possible to detect authenticity Of Client and Server Certificate. For example, If server A has certificate and someone C stolen its certificate and send it to B then How we decide that it's ...
21
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4answers
23k views

how digital signature verification process works

I am not able to understand that how the digital signature is verified. I know that digital signature will be attached to the message and sent by sender to receiver. then receiver uses the public key ...
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1answer
352 views

Installed new Wildcard certificates on my server, but still appear as expired on browser [closed]

I have bought new WILDCARD certificates (*.mydomain.com) for my servers. I was able to install successfully on one server. So, I know the files are correct and I was able to verify their validity. ...
9
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2answers
257 views

Why do some certificates specifically identify a corporation and most don't?

Looking at a handful of websites that allow for/require HTTPS, I realized that the certificate for a few of them specifically identifies the owning corporation, but some (most) don't. What's the ...
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1answer
78 views

Certificate for Email Encryption and signing

I don't understand the flow of Digital Certificate with Email Encryption and Signing. For Example, There is 2 users, Sender A and Receiver B. Is Certificate required to encryption to A or just ...
26
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1answer
18k views

What is the difference between Serial Number and Thumbprint?

I have problems to understand what the difference between the Serial Number of a certificate and its SHA1 Hash is. the MSDN says: Serial number A number that uniquely identifies the ...
3
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1answer
14k views

OpenVPN Tap vs Tun Mode [closed]

I would like to know practical difference between TAP and TUN mode when use with OpenVPN. When to use TAP and When to use TUN ? What types of traffic will pass with both mode ?
6
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3answers
2k views

How and when should I use OpenSSL for IT Security? How do I understand the output?

I'm discovering OpenSSL, and already used it to diagnose a faulty SMTP TLS connection, but I'd like to get a better / full understanding of the tool and how to use it. What resources should I use ...
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2answers
2k views

Digital Certificate “Signature and Fingerprint”

What's the difference between Digital certificate's signature and fingerprint (thumbprint) ? I know that Signature: The actual signature to verify that it came from the issuer. and Thumbprint ...
0
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1answer
1k views

OpenSSL get key length of all certs [closed]

I am trying to ensure that all certificates in a chain for a host have a key length of 2048 bits. Using openssl s_client, only the key length for that host's cert is given, is there a simple way to ...
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1answer
2k views

Sending Client Certificate to Server

I have a simple question. Is a web browser sends client certificate to the web server on demand(means web server is configured for client authentication and demand the client certificate) or just ...
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1answer
559 views

Trying to verify my X509 certificate “could not verify this certificate for unknown reasons”

I have created my own X509 certificate with my own CA. I am able to import the CA certificate into Firefox, but when I try to import the user's certificates i get the following: "Could not verify ...
2
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1answer
5k views

SSLv3 or SSL Certificate Version 2?

Below is the SSLScan output, what does it mean with SSL Cerficate Version 2? Aren't SSLv3 and SSL Certificate Version 2 the same? ...
0
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1answer
366 views

How does ssl prevent MITM attacks [duplicate]

My understanding of how it works : A victim asks for the public key of a server. The attacker just forwards this request. The server now responds with a certificate which contains the Public key. The ...
2
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1answer
164 views

Does Internet Explorer handle Extended Validation properly

I'm reading about Extended Validation (EV) certificates and have a few questions. From what I understand, EV allows domain owners to pay extra for a especially trusted certificate (that the browser ...
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2answers
322 views

Choosing the right X.509 certificate infrastructure for securing LAN communications between a PC and a device

Edit: seems like I was quite hasty when typing in my question at first, so here is an updated version of it. I am developing an application that runs on PCs which are on the same LAN as other ...
0
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1answer
102 views

how does IE or chrome verifies certificate? [duplicate]

If the HTTPS webserver uses self signed certificate, the web browser warns the user as follow. http://www.sslshopper.com/assets/images/iis7/iis7-self-signed-certificate-8-certificate-not-trusted.png ...
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0answers
116 views

What are some good design practices for cross-platform certificate storage?

Question from the Bouncy Castle development list: At present we use the Windows certificate store as: var store = new X509Store(StoreName.My, StoreLocation.LocalMachine); ...
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2answers
110 views

user identity certificate

I want to create a new scheme for user identification, like X.509 certificates, but not X.509. Is it possible to use this new certificate over the existing Internet? and if yes, what are basic ...
2
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0answers
682 views

SSL Certificate Authentication Issue 403.7 [closed]

I have been trying to configure SSL for authentication and was unable to resolve this error 403.7 on IIS 7.5 windows 2008r2 vps server. I would like to give access to few computers where client ...
0
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1answer
408 views

Invalid Certificate when adding Gmail account to Apple Mail

Trouble seemed to start after upgrading to OS X 10.9. I stopped receiving email in an account I'd set up over a year ago. I removed the account and when I attempted to add it again, I was served a ...
4
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3answers
957 views

Web Certificate invalidation - You might be connecting to a website that is pretending to be [Site name]

Recently while trying to log-in to Facebook this notification starts to appear: At first I ignored it (by pressing Continue), but it started to popup every time I navigate through the website! I ...
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0answers
21 views

Error 150 (net::ERR_SSL_PINNED_KEY_NOT_IN_CERT_CHAIN): The server's certificate appears to be a forgery [duplicate]

Can you tell me shortly how to fix this problem in Chrome? Error 150 (net::ERR_SSL_PINNED_KEY_NOT_IN_CERT_CHAIN): The server's certificate appears to be a forgery
14
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2answers
2k views

SSL fingerprint inconsistency: what does it mean?

I apologize if this is not the best place to ask my question on the stackexchange network, I couldn't figure out where to get enough attention and be relevant. Facebook provides a SSL host, it can be ...
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2answers
245 views

Understanding certificate security

I am reading Computer Networks by Tanenbaum and Weatherall. In chapter 8 they describe secure communication using public key exchange via certificates. They describe a situation where Alice is sending ...
2
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2answers
3k views

Basic self-signed certificate questions

A few basic questions around self-signed certificates Question 1 Does a self-signed certificate has to have a CA? I realize that a "real" certificate must as it otherwise can be chain validated but ...
29
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5answers
15k views

Where to get an SSL certificate for personal website?

I would like to use https to login to my personal webpage (which is on shared hosting). So I went over to google and started searching for sollutions. Eventualy I found out that I need an SSL ...
2
votes
1answer
729 views

question about implicitly tags in ASN.1

From the X.509 RFC, in the "Implicitly Tagged Module" section: CRLDistributionPoints ::= SEQUENCE SIZE (1..MAX) OF DistributionPoint DistributionPoint ::= SEQUENCE { distributionPoint [0] ...
3
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4answers
343 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 ...
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3answers
736 views

Can we make sure that the new Lavabit certificate is not under control of the FBI?

After the Lavabit shutdown, Ladar Levison (founder of Lavabit) announced that he’s "looking into setting up a site where users can download their data". Such a site is now online: ...
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1answer
637 views

Additional security for WebRTC/DTLS-SRTP with PGP?

I am having a thought experiment. Can you help me? Two clients who both use PGP. They initiate a WebRTC call using DTLS-SRTP via a 3rd party server. Is there any benefit of encrypting, via their ...
3
votes
1answer
119 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 ...
4
votes
4answers
839 views

Is it possible to detect SSL private key changes?

I wonder if it would be possible to detect a change of an SSL private key? If you change the key, then I think one must issue a new certificate, but new certificates could be issued without changing ...
2
votes
3answers
278 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 ...
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1answer
116 views

Certificate Mapping in IIS

When pasting the certificate blob in the configuration editor in IIS 7.5 for one on one authentication, is this the server certificate or the client certificate?
3
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1answer
184 views

FIPS compliant application based on OpenSSL

Let's say I need to write a simple application for signing/checking some data. The hard part is, that it must be FIPS 140-2 compliant. I was thinking to do it using OpenSSL FIPS Object Module 2.0 but ...
4
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1answer
924 views

Is possible that a TLS server send more than one certificate to the client for the same site?

What I'm trying to archive is enable ECDSA and DSS ciphers in my site, but at the same time not depend just of self signed certificates, so I could sent to my client more than one certificate and them ...
1
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2answers
120 views

non-MiTM Reverse SSL

Do non-MiTM Reverse SSL Proxies exist? Or do all proxies that do SSL-SSL mappings decode and then re-encode HTTPS traffic? If this is the case and I want to map https://mypublicdomain.com -> ...
2
votes
1answer
2k views

Evaluate the signature of an X509 certificate in .NET

This is my scenario: A CA signs a certificate with its private key and sends it to a client via https response. From this response the client creates a X509Certificate2 class, that represents the ...
2
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1answer
124 views

What are the benefits (if any) of changing TLS certificates frequently?

As I understand it, a certificate is used only for verifying the identity of the server. Are there any security benefits for changing them frequently (once a week for example)? If this is done so ...
11
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1answer
510 views

Is using a CA more secure if I'm self-signing anyway?

We have a web application that we run for clients at their booth on fairs. The communication between clients and the server was done over HTTP until recently. We're currently working on improving ...
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vote
3answers
375 views

Where can I find all SSL CA certificates

I am working on an SSL implementation project and ofcourse I need to verify the certificate presented by the server. To do that I need CA certificates or at least root CA certificates (correct me I am ...
3
votes
2answers
351 views

Requirements for qualified certificates in DIRECTIVE 1999/93/EC

DIRECTIVE 1999/93/EC at ANNEX I Requirements for qualified certificates states that one requirement for qualified certificates is (a) an indication that the certificate is issued as a qualified ...
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3answers
4k views

How does an SSL server prove its identity?

This document says that a challenge response authentication proves the servers identity. But is a man in the middle attack still possible if the client does not verify domain name ? Please help me ...
4
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1answer
104 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 ...