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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HTTPS self signed certficiate for personal website

I want to make my Synology NAS accessible over the internet. When I create my own certificate and import this on all my devices (PC, Laptop, Smartphone, Tablet, etc.) is this as secure as buying a ...
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Does Google use extended validation certificates?

I just changed a password on a Google account while using the Chrome browser. After doing so, I noticed that the https connection to Google was not highlighted in green signifying that it was an ...
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264 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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Is there any way to get Chrome 27 to trust a self-signed cert? [closed]

I'm running latest gen Chrome (27) and preparing a demo that requires using a self-signed cert to support HTTPS on a local IIS website. The cert has been created with the correct common name for the ...
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security of PKI, Certificates, certificate authorities, forward secrecy

I want to understand how certificates add to the security of information exchange. Suppose i have a encrypted bidirectional connection between Alice and Bob, using a public key/private key pair. As ...
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664 views

What are the problems with creating an own CA for intranet?

In the comments to Creating my own CA for an intranet several people strongly advise against creating your own CA for an intranet. Especially: don't do it. Nope. Bad idea. Buy $10 CA signed ...
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When you buy a certificate, does the certificate authority have (a copy of) the private key?

I always assumed that the process for getting a (trusted, not self-signed) certificate was more or less like this: You generate a public and private key pair From this key pair you generate a ...
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Adding self signed certificate to trusted store

I have been reading about certificates and often is said that self signed certificate should not be added to the trusted authority store and even if you did, remove it after usage immediately. MSDN ...
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852 views

Do client certificates need to be trusted by the client?

I'm looking for some clarification around the trust requirements (if any) of client certificates. I'm working with a third party to access their services via Mutual TLS. I generate a CSR, send it ...
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Getting a Root CA accepted in systems and browsers

I would like to ask about the procedures for a given CA to get one of its root CAs (SSL issuance CA) to get accepted and installed as a trusted root CA in operating systems and browsers.
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Understanding SSL certificate signing

I am trying to understand how SSL certificate and signing and the chain of trust works. I know about root CAs and that they are used to sign intermediate CAs that sign the end certificates that are ...
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Obtaining an S/MIME certificate without disclosing my private key to the TTP

I would like to obtain a trusted S/MIME certificate, but all the certificate authorities I have asked so far generate the keypair on their server, sign the certificate and send me both the private key ...
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433 views

Why is there no Domain CA?

I was asked to deliver a signed SSL certificate for an IIS server for a client. I have previously done this for the same client/domain before, so it start to seem like an unnecessary expense to hold ...
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1answer
545 views

Why does GoDaddy have four different certificate chain, G2, G3, G4?

I see from Godaddy they have multiple certificate chains https://certs.godaddy.com/repository GoDaddy Certificate Chain GoDaddy Certificate Chain - G2 GoDaddy Certificate Chain - G3 GoDaddy ...
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7answers
319 views

Proving running code on a website is unchanged

Can it be proved to the user that the running code behind a website with security related code is the same as published? I'm currently looking at a few new project ideas and one involves secure ...
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2answers
898 views

How is an HTTPS login secure when pages use HTTP?

When someone go to eBay's website, they use an unencrypted connection between their PC and eBay's server. If they sign in, they are redirected to a secure site identified by its certificate and may ...
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1k views

Certification authority only for certain domains

Is it possible to make a certification authority certificate (even unsigned), which only allow to sign certificates for specific domain(s)?
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781 views

What kind of certificate do I need to be able to sign my own subdomain certificates?

We are making a web-based application that will be installed in intranets as a virtual machine image (we send the user a CD with the virtual machine image, user runs it in a VMWare/VirtualBox/...). ...
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3answers
560 views

Are there any smartcard/hardware-tokens for certificate-based authentication which are easily destroyed?

It's all very well to use multi-factor authentication, but supposing you want to 'destroy a factor' so that in an situation where you are likely to be coerced to provide your passphrase, you can ...
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1answer
389 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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34k views

Is there an SSL / TLS Certificate state-cache on Windows, IE, and Outlook and how it it managed?

Today I changed the SSL certificate that 3,000+ Outlook clients are using. In doing this I changed the certificate to an "older" one that had the same subject name, expiration and everything else. ...
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2answers
793 views

PKI solution vendor selection

What would you look for in a (X.509-) PKI solution, and why would you look for that, given the following constraints: Available programming/sw-engineering know how is limited (ie, "OpenSSL with a ...
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3answers
324 views

Would using distinct IP addresses help support browsers with older SSL implementations?

We have a site with two wildcard certificates: *.foo.com and *.bar.foo.com. All of our subdomains resolve to the same IP address. Newer browsers work fine with this, but IE7, for example, does not. ...
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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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6answers
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I see two different sets of certificates for Google websites when I am at work and when I am at home

I see two different sets of certificates for Google websites when I am at work and when I am at home. I mean if I save the certificates (in firefox, click on the "Google.com" block on the left of ...
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14k views

SSL certificate chain verification

After reading many articles and watching many tutorials I decided to be specific because there are some things about SSL certificate chain verification and SSL cetificate verification in general that ...
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How trustable are third party root certificates?

I recently tried to use Fiddler2 from a third-party vendor Telerik. While decrypting the HTTPS traffic of my network, it asked me to install its own root certificate in my Windows operating system: ...
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887 views

Why the symmetric key is added to the message?

Yesterday in my class we learnt how to send a message from Alice to Bob with the achieved goals of confidentiality, integrity and authenticity. In order to have a better performance we use a hybrid ...
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Internal SSL Certificates?

As a developer I really like the idea of using OpenSSL to get perfectly good, free, SSL certs. Unfortunately, from all the research/analysis I've done so far, it doesn't look like there is any way to ...
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What web browsers support OCSP stapling? Are the privacy and performance features the same?

OCSP stapling decreases the load on a PKI infrastructure's OCSP server by attaching a signed OCSP response to the target in a TLS connection. In addition it creates a more secure/private session ...
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594 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, ...
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2answers
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How is certificate forgery with cheap CA's prevented?

In order to perform a successful man in the middle attack on HTTPS, one needs to either strip SSL layer and convert it to HTTP completely or needs to have a valid certificate from a CA for the same ...
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1answer
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How does adding a random serial number improve a certificates' security?

This article says: "Finding collisions is a tricky process, since it requires you to muck with the bits of the public key embedded in the certificate (see this paper for more details). Also, ...
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293 views

Why are website certificates secure?

I understand how HTTPS connections work, and I also understand they they require a certificate to know that the secure connection you have is with the right server (and not someone pretending to be ...
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2k views

What are the benefits and drawbacks of the HTML5 Keygen element?

As of January 2013, what are the potential benefits and drawbacks of the HTML5 Keygen element?
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What damage could be done if a malicious certificate had an identical “Subject Key Identifier”?

I'm looking at the the Subject Key Identifier attribute of a CA certificate and am trying to understand the role it plays in validation and infer how validating client software could get it wrong. ...
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3answers
884 views

Does the SSL encryption strength or validation level of a website really matter?

When looking to get an SSL certificate one is presented with a lot of options. For example lets take Network Solutions since they have a nice comparison chart. Immediately there seems to be 4 major ...
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1answer
407 views

How to use encryption on a site that only uses an IP address, no domain name?

You can use SSL/TLS certificates and etc. on sites with domain names, but I don't know if it's possible to use them for IP addresses. If this is the case, would I have to use a self-signed cert and ...
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619 views

Did scammers take control of a subdomain to host phishing site?

This morning I received a text message (ostensibly) from my bank: We need to contact you. Please visit https://paymentassistance.nationwide.co.uk for more information My spidey sense immediately ...
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Alternative to “web of trust”

Let's say I have an SMIME platform where I want to easily establish trust across the entire world for a particular purpose, for example for sharing valid financial information. I think that a ...
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1answer
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Why do X.509 certificates have “Key Usage” attribute?

I can find their values and all details in the RFC, but I cannot find why it was decided to have this attribute in certificates, instead of leaving them to be multipurposes. Is there a reasoning ...
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How do I store Diffie-Hellman parameters in a X.509 certificate?

In there paper Authentication and authenticated key exchange Diffie, van Oorschot and Wiener recommend to insert the DH parameters into the certificate of Alice. As a result an attacker can not change ...
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X.509 certificate policies question

I asked another question about certificate policy mappings. This is a different issue. This is about Certificate Policies. To quote from the X.509 RFC: In an end entity certificate, these ...
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1answer
377 views

distributing files to VPN partners

suppose i've created VPN certificates for a certain VPN-RoadWarrior-Client, expressed in the files VPN-RoadWarrior-Client.key and VPN-RoadWarrior-Client.crt*, however VPN-RoadWarrior-Client is ...
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179 views

What kind of certificate should I get If I want to secure a connection between a web server and a database?

I know people buy SSL certificates to secure their sites. What kind of certificate should I get if I want to encrypt a connection between an application server and a database? Application server may ...
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1answer
477 views

How can I verify if a website revoked its old SSL certificate keys? [duplicate]

Through reading from multiple sources and watching Security Now's How the Heartbleeds, I have come to the understanding that the following procedure is recommended to be safe from the Heartbleed ...
8
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1answer
148 views

Browser blacklists & the Symantec-Google Certification Debacle

Background: As explained e.g. on this Google company blog, Google writes that: On September 14, around 19:20 GMT, Symantec’s Thawte-branded CA issued an Extended Validation (EV) pre-certificate ...
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1answer
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Moving from a one tier to a two tier Microsoft Certificate Authority hierachy

Right now we have a single Microsoft Enterprise Root CA which issues certificates to our VPN users for two factor authentication. We're planning to extend use of the CA to issue certificates for RDP ...
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117 views

“Manually” verify a certificate

I want to 'manually' verify a certificate and the first step in doing so, I accessed paypal.com and obtained the following RSA modulus and signature value. modulus = ...
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142 views

What considerations should apply for self service Renewing, Revoking, or Unrevoking a certificate?

I need to design a self service portal for renewing, revoking, and unrevoking a certificate and have come up with the following rules*: Renewal Certificates have a short term validity and need to ...