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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228 views

search CA for someone's public key

do CAs offer service wherein an application can request someone's public key? i am trying to do this but i am unsure if it is correct (suggestions of better ways to do it will be most appreciated): ...
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2answers
1k views

Does critical SubjectAltName IP:x.x.x.x on an SSL client certificate limit where the certificate can be used from?

I have a requirement to limit SSL certificates by source IP. Would setting a critical SubjectAltName limit this (server side validation is by OpenSSL via nginx)? If not, how could this be ...
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2answers
6k 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 ...
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1answer
996 views

Who is this strangely named Certificate Authority?

I'm researching certificate authorities, and I just have no idea what to think of the CA named x00Ax00-x00Tx00rx00ux00sx00tx00 x00Gx00ex00sx00.x00 x00fx00xFCx00rx00 ...
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1answer
178 views

What do people mean by “top-down manner” in X.509 certificates?

What do people mean by saying that X.509 certificates work in "top-down manner"? Do they say that because CAs can do cross certifications?
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4answers
251 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 ...
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0answers
44 views

Writing Security Functionality Requirements [closed]

Is there any Guideline Doc. or Tutorials for writing Security Functionality Requirement (Common Criteria)for a product?
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4answers
2k views

How to check if wifi is safe while travelling?

I'm quite a bit of a traveller. So i tend to just stay with my smartphone and sometimes notebook. I'm not a security expert but i would like to check how to know if wifi is safe to use. For example, ...
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1answer
5k views

Why is a CA certificate required for EAP-TLS clients?

When setting up clients with WPA2 EAP-TLS, most clients (ie: my phone, my computer) require both a client public/private keypair (for obvious reasons) and a certificate authority certificate. It's ...
7
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1answer
265 views

Which signing key should I use for certifying other peoples public keys: master or subkey?

I have a Master Identity key (which is detached from my daily-use keyring) and both encryption and signing subkeys (all are RSA). I sign documents with the signing subkey: GnuPG selects this key ...
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1answer
1k views

How does Windows/IIS keep a certificate protected or should I never run Apache Webserver on a Windows server?

If I follow the reasoning of a colleague it seems you should never run Apache Webserver or Tomcat on a Windows server if you want to keep the https certificate safe. Let me explain before this ...
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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 ...
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1answer
611 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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1answer
2k views

Client certificate for 2 way SSL works in some programs, and fails in most

I am trying to establish 2 way SSL connection with remote server and I have received certificate to connect. Can somebody explain behaviour described below. I am able only to use it with SOAP UI ...
2
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2answers
268 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 ...
4
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3answers
517 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, ...
2
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3answers
472 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?
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2answers
2k views

How To Recover EFS Cert From Backup?

I made a backup of the old Win 7 Pro then did a clean install. But I forgot to export my EFS encryption certificate, so when after I restored the encrypted files from backup I could no longer access ...
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1answer
332 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
256 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
76 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 ...
3
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1answer
13k 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 ?
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2answers
267 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 ...
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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 ...
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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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3answers
1k views

Client Authentication by certificates in Google APP Engine java

I am writing an application in Google APP Engine java which authenticate the user by its certificate. I have created a self signed certificate using keytool at client side. I also enable the HTTPS ...
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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? ...
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2answers
892 views

Windows certificate store suddenly changed security level of one of my certificates

I use Windows 8.1 Pro 64 bit and IE11. I have two personal certificates (with private key) of mine in the system certificate store. They are both set to require a password before they can be used. ...
0
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1answer
307 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 ...
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1answer
506 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
160 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 ...
0
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1answer
98 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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2answers
301 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 ...
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4answers
4k views

Why can SSL certificates not be free of charge?

I am a newbie in this field. I am confused with why SSL certificates cannot be free of charge. In my understanding the certificate is just a text file consisting of cryptic numbers installed on a ...
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0answers
112 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
101 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 ...
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0answers
630 views

Safe communication via rest api between two known servers

I'm using Kinvey as backend but because it doesn't provide the ability to run custom code I have set up another server. So basically when x happens on Kinvey server, I send a call to my rest api on ...
0
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1answer
402 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 ...
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1answer
896 views

Convert a DER encoded Certificate to PEM encoded Certificate

I have a p7b certificate(DER encoded) which I need to convert to a PEM encoded certificate so that I can import it into my keystore. I see that the openssl command below does the job of the ...
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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
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2answers
237 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
2k 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 ...
5
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2answers
9k views

Openssl generate different type of self signed certificate

Does anyone know how to use openssl to generate certificate for the following public key type: 1) DSA - For DHE_DSS key exchange. 2) Diffie-Hellman - For DH_DSS and DH_RSA key exchange. 3) ECDH - For ...
3
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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 ...
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1answer
607 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 ...
10
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3answers
734 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: ...
0
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1answer
3k views

Problems with intermediate ssl certificates and ssl proxy

I'm currently implementing a SSL-proxy, and have run into some problems regarding certificates. We have a offline "Company Root CA", and an online "Company intermediate CA". On the proxy I have ...
2
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3answers
260 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
112 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?