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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169 views

Is there any mechanism to audit which signed certificates are unrevoked?

We are currently using EasyRSA and OpenSSL to manage our user VPN certificates for OpenVPN. The process we have in place currently is: User generates a CSR on their laptop and sends it to us to sign ...
2
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2answers
228 views

Client Authentication Certificate Not Expiring, but “parent” cert IS

So I have a client-authencation cert installed on client PCs, which doesn't expire for 5 more years. Unfortunately, the cert on our gateway which is used to validate the client cert, expires this ...
2
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3answers
178 views

Are Extended Validation certificates any more secure than regular ones?

Or are they just an attempt to get you to pay more money to a CA because it tells your browser to show the address bar in green with your organization's name? Also, what are the technical details ...
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2answers
514 views

Is Certificate pinning different from CA pinning?

I am trying to understand if pinning a certificate essentially means pinning the CA or if they are different how so ?
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2answers
85 views

Which signing strategy?

I have a device which should lock and unlock something after receiving a signed server response. So in the best case a loop would lock like this: User locks device User wants to unlock device User ...
2
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2answers
743 views

Looking for general guidance on securing web API application for client applications and users

I have a web service built with WebAPI that accepts JSON requests and responds accordingly. The core architecture is built but there isn't any authentication/authorization. After a lot of googling ...
2
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1answer
3k views

Does Java's implementation of OCSP and CRL checking handle intermediate CAs?

I've read that Java provides OCSP and CRL checking for CertPaths via: Security.setProperty("ocsp.enable", "true"); System.setProperty("com.sun.security.enableCRLDP", "true"); Do these implementations ...
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2answers
2k views

Difference between Encryption and Verification certificate

What is the difference between the Encryption certificate and Verification certificate in Outlook? When exchanging certs, it just requires a digitally-signed message to be sent. It seems as though ...
2
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3answers
451 views

Forged SSL without installation of root CA, possible?

Consider visiting a secure website like Gmail. Is it possible to forge the website certificate only by having full control over the internet provider? I mean is it practically possible for a provider ...
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4answers
3k views

Does a renewed certificate open old messages?

I have a digital certificate that I use to exchange messages with peers, my certificate expiration date is due next year, suppose I renew this certificate before it expires, will I be able to open the ...
2
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3answers
253 views

Whether certificates can be used for regulating access

I am thinking of a mechanism where I need to authenticate the client and control the access. I am thinking of using SSL for this purpose. I want to know whether using SSL solves my purpose. My ...
2
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1answer
1k views

X.509 certificate policy mapping question

So I'm a little confused how X.509 certificate policy mappings work. So let's say the following depicts my cert chain: root CA ---> intermediary CA ---> client cert Would the root CA have a ...
2
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1answer
564 views

Does client certificate authentication demand more server-side entropy?

We have a secure web service running Apache that requires client certificates for access. This service has a problem with running out of entropy. We have several other sites that use TLS that get ...
2
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1answer
302 views

Snapchat tracking over company WiFi. What can they see, save or open?

I sent a snapchat to a coworker during company time. I was not on the work wifi, but now I believe they may have been. What will my employer be able to see from the snapchat that was sent and opened ...
2
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3answers
263 views

Why doesn't openssl s_client correctly validate google.com:443?

I try $ openssl s_client -connect www.google.com:443 but it openssl complains that the cert chain is invalid: $ openssl s_client -connect www.google.com:443 CONNECTED(00000003) depth=2 C = US, O = ...
2
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1answer
129 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 ...
2
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1answer
156 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 ...
2
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1answer
109 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 ...
2
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1answer
2k 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 ...
2
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2answers
63 views

How does Certificate Transparance detect fake or forked logs?

I am trying to understand Certificate Transparency. Let's say I want to snoop on somebody's email. So I go hack or bribe a CA, have them issue a certificate for google.com, and then I present it when ...
2
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1answer
148 views

Attribute Certificates and Access Management

I recently came across Attribute Certificates (RFC 5755), which can be used as a means for authorisation. I like the idea but I have spent a lot of time searching for information how this works in a ...
2
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1answer
390 views

EC private key, RSA certificate. Is this realisable?

I was wondering if is it possible to generate EC private key: openssl ecparam -name sect571r1 -out ecparam.pem openssl ecparam -in ecparam.pem -genkey -noout -out eckey.pem then generate ...
2
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3answers
362 views

HTTPS client certificates for server-to-server

Say you have two servers with certificates proving their domains (e.g. for use with HTTPS). Can one of these servers use their certificate as a client certificate when talking to the other, so that ...
2
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1answer
306 views

A certificate site name mismatch when using preinstalled Toshiba software? (Superfish?)

On my Toshiba laptop there are a variety of different Toshiba programs that came pre-installed. Many of them are some sort of utility, optimizer, checkup, and update kind of programs that I guess are ...
2
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2answers
303 views

Does Ephemeral Diffie-Hellman require a certificate?

In Ephemeral Diffie-Hellman, the key pair is generated every time. In practice, does this mean I never need a certificate? Or that means I need a new cert every single time?
2
votes
1answer
566 views

How to make a decent Certificate Signing Request (CSR)?

I'd like to know how to make a decent Certificate Signing Request (CSR) to secure my website and e-mail with a wildcard SSL certificate. With recent exploits as POODLE on SSLv3 and such, I'd like to ...
2
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1answer
9k views

How to get SSL certificate of a mail server?

I need to get SSL certificate of some mail servers. I know I need to do execute following steps. Do a DNS mx query on the domain name (dig google.com mx). Use the information to download SSL ...
2
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1answer
174 views

What does verified file in windows mean? And does it guarantee related files?

Often when I run a .exe file in Windows, a small box pops up that shows that file is from a verified publisher (e.g Microsoft) or in other case, unknown publisher. I know public key encryption can ...
2
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2answers
161 views

Authentication through digital certificates plus signature

While studying X.509 certificates, I've found that authentication is safer if I associate/combine one or more certificates with each signed message (certificate + signed message). The receiver of ...
2
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3answers
143 views

How are public key certificates updated securely?

Let's say I get a new computer that's never been connected to the internet before. The first time I connect it to the internet, is it susceptible to a mitm attack while downloading its public key ...
2
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1answer
201 views

Why does facebook php sdk (and multiple others clients) include CA bundle with a lot of CAs?

This is what facebook ships with their API php client: https://github.com/facebook/facebook-php-sdk-v4/blob/master/src/Facebook/fb_ca_chain_bundle.crt It contains dozens (hundreds?) Root CAs. But ...
2
votes
1answer
118 views

How does checking CRLs make sites less safe?

With the frantic certificate upheaval resulting from the Heartbleed fiasco [drink!], there has been lots of talk regarding certificate revocation, and in particular the policy of certificate ...
2
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1answer
429 views

How secure is PKCS #12

I need to move user cryptographic identity between several user devices. In the operating system I have only one option: use password-protected PKCS #12 to import the identity to the OS secure store. ...
2
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1answer
222 views

SSL certificate to protect spoofing of API server

I have a program written in Python that checks the validity of its license key with a remote server. Am I right that an SSL certificate would make it possible to prevent spoofing (host redirects for ...
2
votes
1answer
3k 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
votes
1answer
139 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 ...
2
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2answers
716 views

Wildcard SSL Certificates & SAAS

From what I have read, using a wildcard SSL/TLS certificate is not advisable, how do you do certificate issuing & management in your SAAS application(linux) where each client has a user selected ...
2
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1answer
531 views

Security Certificates - Tools to Generate Security Certificates

I want to create a self-signed certificate that will be installed as a trusted certificate authority. I then want to create another two certificates which are signed using the private key of the self-...
2
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1answer
240 views

How does a function certificate work?

Say that we have a client / server solution (written in .NET). If we want to use a certificate for the TCP communication, is it enough to use one function/service certificate to encrypt communication ...
2
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2answers
719 views

SSL: How to send generated client certificate from server to avoid MITM?

The question I have is simply how do I prevent a MiTM attack on a certificate once the server side creates a new one and tries to send it to a client? Does the certificate get encrypted by rsa and ...
2
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2answers
6k views

HTTPS verification failed - get certificate information iPad/iPhone

I went to log onto my bank's internet banking website this morning using Google Chrome browser on my iPad. I get the red error message of death. I can't figure out why. It's happening on both my iPad ...
2
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2answers
799 views

How do I verify, parse and process the results of the HTML5 keygen tag?

I'm investigating the HTML5 attribute Keygen and discovered that it sends this data on a Form POST to the server. Here is an example POST: ...
2
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2answers
1k views

Revoked certificate validation using past times

I'm working on XAdES implementation for Java, as such I require cryptographic implementation to be able to verify certificates in the past. Unfortunately I have problems verifying revoked ...
2
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1answer
378 views

Signature and Timestamp for Long Term Document Archival Question

I have a PDF document intended for long-term (many years, maybe decades) archival which I would like to digitally sign with my personal certificate to ensure its integrity. As far as I understand, I ...
2
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2answers
2k views

How to use 'key material' so that multiple people can access protected files?

I'm not sure if this is the right SE to ask this question, but it seems more I have a database of files that needs to be encrypted such that multiple people with different passwords/logins to this ...
2
votes
1answer
135 views

CSR generation origin?

Platform: Windows 7 x64 Development: .NET 4 Web Server: HttpListener (IIS not installed, will not be installed :) ) Can Machine A generate a Certificate Signing Request for Machine B and have the ...
2
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2answers
55 views

CA Certificate Lifecycle

I'm planning to implement a new PKI with 2 tiers of CAs. I'll have end entity certificates with a lifetime of up to 5 years. This means my Issuing CA should be valid for 10 years, in order to be able ...
2
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1answer
69 views

Can I revoke a client certificate using only it's serial number (not it's crt/pem)?

I've signed and issued some client certificates with my CA. I can now revoke them like so: openssl ca -name ${CA_NAME} -revoke ${USERS_DIR}/${USERNAME}.crt -keyfile $SSL_PRIVATE_DIR/ca.key -cert $...
2
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1answer
81 views

How do “certificates” hold “keys”? [duplicate]

I am new to the realm of security and keep hearing about "certificates" containing "keys". But no one has been able to actually explain to me what is actually meant by this. I assume that the ...
2
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1answer
87 views

DNSCrypt-proxy: This certificate looks valid

I have just installed dnscrypt-proxy and dnsmasq with DNSSEC but I get a strange message in the logfile from dnscrypt-proxy. [INFO] + DNS Security Extensions are supported [INFO] - [dnscrypt.eu-dk] ...