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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35
votes
10answers
11k views

Is anybody using client browser certificates?

Client browser certificates seem to be a nice way to protect sites from intruders - it is impossible to guess and should be harder to steal. Of course, they do not solve all the problems, but they add ...
0
votes
1answer
26 views

Creating self-signed certificate for localhost and trusting fully

As an accompanyment to a web application we plan to have a node application running as a windows service running on the client computer. This will run a small web server which will listen on port XXXX ...
2
votes
0answers
21 views

How to enable self signed certificates in Windows 10?

I want to use a Yubikey 4 with Windows 10 Pro for Bitlocker and login with my TPM. Unfortunately, I found out I need to enable self signed certificates and all the guides on the Internet I found were ...
13
votes
2answers
2k views

Are SHA-2 certificates considered obsolete, or current?

A guide on this site on how to make a decent Certificate Signing Request (CSR) says that I should be using SHA-2 certificates to secure a HTTPS webserver. Are SHA-2 certificates considered obsolete, ...
3
votes
1answer
45 views
+100

X509 CRL suspended certificates and openssl ca comand

In CRL X509 format we have "Hold Instruction code" for a list of suspended certificates. I know that "its use is strongly deprecated for the Internet PKI", but in my own private CA, I want to use it. ...
1
vote
0answers
15 views

How did I get a signed cert back with a wildcard common name when I submitted a csr with a specific common name? [duplicate]

Apologies if this is obvious but I'm hoping for some clarification here. I generated a CSR on an appliance of mine. This CSR had a specific common name (let's call it foo.domain.com). I then sent ...
5
votes
1answer
120 views

How To Bypass SSL pinning In SPDY protocol?

I have been trying for almost a month to intercept the traffic of an android app the uses SSL pinning. I used Android-SSL-TrustKiller and SSLUnpinning but it did not work.I also decompiled the app and ...
-1
votes
1answer
40 views

Same certificate but different private keys on different servers. Does this work?

We have a SAN cert that is used on multiple servers. Is it possible to have the cert re-keyed and only use the new private key on a particular server while keeping all of our other servers using the ...
0
votes
3answers
54 views

Same wildcard cert from two different 3rd party CA's

We have a wildcard cert that's due to expire in three months. The CA won't let us renew it until one month prior to its expiration. We're thinking about using a different CA since we've since ...
4
votes
2answers
51 views

Trusting the “subject” of an x509 certificate

A bit of background. Our organization is working on a document format that will be ingested by our software. We're using the CMS format to verify the integrity (by validating the signature). The CMS ...
3
votes
2answers
69 views

Best practices to implement HTTPS in embedded devices

Embedded devices, such as routers, IP cameras, generally provide HTTPS access to the admin interface. These HTTPS implementations generally have a lot of problems (non-unique certificates, self-signed ...
3
votes
3answers
192 views

How to check if I have a rogue SSL/TLS certificate?

It's known, that if someone manages to install their certificate as a trusted certificate on your Windows computer, they can read all you SSl/TLS traffic with man-in-the-middle attack and you won't ...
4
votes
1answer
109 views

Bidirectional encrypted server to server communication using TLS

I have 2 Windows servers and would like to set up encrypted communication between them using TLS. I've been reading up on TLS and X.509 certificates and I think I have a reasonable plan, but would ...
1
vote
1answer
211 views

Distribute S/MIME public keys and CA cert for email security

I have my own CA. I want to distribute S/MIME certificates for 10 different users. I saw S/MIME keyservers from http://wiki.cacert.org/KeyServers, but I don't want to use public servers. What is the ...
1
vote
5answers
83 views

Best Option for SSL Certificate for 2 Domains + All Subdomains

I am hosting multiple websites on my Mac Mini server (latest version). For some reason OS X server does not support multiple SSL certificates well for websites, and after hours on the phone with ...
0
votes
1answer
20 views

How secure is it to bundle unencrypted private key and a CSR into PKCS12 certificate?

I want to create a self-signed certificate to digitally sign my documents. I want to do so using my existing key pair, but to accomplish this I'd have to export my private key unencrypted into a file, ...
0
votes
1answer
39 views

Securing Internal Mobile REST API

I am planning to create an internal API for mobile devices for a company. They are planning to use this internal mobile app to get data from custom ERP, uploading contract, etc. Thus, it will be ...
1
vote
2answers
78 views

Certificate handling on a small network VPN

Background - I need to set up secure remote access for a small home office. I'm a bit of a noob and haven't needed to handle certificates before. I understand most of the setup but I want to ...
4
votes
1answer
137 views

TLS connection to untrusted server - client reaction for dropping connection standardized?

I played around with a man-in-the-middle proxy tool and connected different smart phones to it. As the proxy uses a self signed certificate the tested smartphone apps did not accept the presented ...
1
vote
1answer
37 views

Securely opening an insecure webserver to a single phone

I have a webserver running inside my private network and not exposed to the internet. I'd like to securely talk to this webserver from my mobile phone over the internet. However, this webserver has ...
0
votes
0answers
16 views

Does the AppId matter when self signing a cert?

We are going to start using self-signed certificates on our dev server. I went through some step-by-step instructions on how to generate the cert and set up ssl with my service. To add the cert, I ran ...
18
votes
3answers
3k views

Let's Encrypt for intranet websites?

Many companies have intranet websites that are not reachable via the internet. Usually they just use a self-signed certificate, which causes a bad habit for the users since they get used to just ...
2
votes
1answer
615 views

Determine private key size using public certificate [duplicate]

I have a public certificate in a PEM (.pem) file -----BEGIN CERTIFICATE----- MIICsjCCAZqgAwIBAgIJAMA1YIQ2JLXDMA0GCSqGSIb3DQEBBQUAMBExDzANBgNV ... 29V/R9RZOoSBHDzGPL84wm4qojMuwQ== ...
7
votes
2answers
758 views

How do systems protect against a stolen code-signing certificate after the certificate expires?

Imagine this scenario: 1st December 2014 - a certificate is stolen and used to sign malware with 2014-12-01 timestamp. 15th December 2014 - the certificate is revoked. Malware will be prevented from ...
3
votes
1answer
97 views

Benefits of a wildcard vs per-subdomain certificates

As you might know, Let's Encrypt doesn't offer wildcard certificates and it won't in a short-term because you can just order as many certificates as you want for the sub-domains. This make me ...
1
vote
3answers
129 views

What SSL certificate do I need?

I have 2 domains, one where the website is hosted (lets call it www.a.com), and another (lets call it www.b.com) which has a CNAME record pointing to the first one (www.a.com). Which one should have a ...
28
votes
4answers
40k views

Expired SSL Certificate Implications

What are the security implications of an expired SSL certificate? For example if an SSL certificate from a trusted CA has expired will the communication channel continue to remain secure?
7
votes
4answers
5k views

Clarifying self-signed certificates vs root certificate authority

I hope someone can help me understand some fundamentals on SSL certificates that I've had trouble picking up from docs, Wikipedia, and just about everywhere else on the internet. I'm working on an ...
1
vote
2answers
69 views

Generating a Certificate Signing Request for an Apache webserver on a sub domain?

I'm reading the instructions for generating a CSR, and it reads that: "Replace yourdomain with the domain name you're securing. For example, if your domain name is coolexample.com, you would ...
5
votes
1answer
64 views

Why are short-lived certificates so rare?

Let's encrypt recently left beta and limits the maximal life-time of certificates to 90 days and recommends 60 days. Now whenever I start talking about the issues of certificate revocation (e.g. OCSP ...
4
votes
3answers
202 views

what do you do when an ssl certificate expires and your app uses ssl pinning?

I originally posted this question on StackOverflow, but reposted here due to lack of responses. I am trying to decide if it's a good idea to do ssl pinning in my iOS game that uses a server to ...
1
vote
2answers
114 views

sftp first connection before exchange cert

If a client connects for the first time to a server via SFTP, the first connection before receiving the server certificate is transmitted in the clear?Let me explain: it is assumed that the client ...
1
vote
1answer
58 views

Can Passpoint X.509 certificates be used to MITM SSL connections on Passpoint networks?

Passpoint/Hotspot 2.0 public networks like LinkNYC require users to install X.509 certificates, for EAP authentication. Can these certificates be used by the provider to execute man-in-the middle ...
0
votes
1answer
49 views

Digitally signing a document with your public/private keypair without certificates?

I have generated a private/public key pair using gpg. Can I use this key pair to digitally sign a PDF without a digital certificate, but to still have the signature integrated into the PDF, instead ...
662
votes
3answers
341k views

How does SSL/TLS work?

How does SSL work? I just realised we don't actually have a definitive answer here, and it's something worth covering. I'd like to see details in terms of: A high level description of the ...
3
votes
0answers
73 views

SSL certificate and price difference [closed]

After reading this discussion, Why are there very expensive and cheap SSL same type certificates? I surfed over the internet “Symantec Secure Site Pro with EV SSL Certificates”. I found something ...
3
votes
1answer
3k views

Is keystore file(server.jks), my private key file?

My task is to convert .p7b to .pfx. It would be great, if you could provide me some pointers. Below are the steps I did to generate .p7b file. I generated jks(java keystore) file using below ...
4
votes
2answers
4k views

Windows Firewall Connection Security with Certificate

I've been fiddling with the Windows firewall configuration of some computers within a VMWare based LAN (no domain). To aid in my testing and debugging, I created a small, self-hosted console ...
2
votes
2answers
67 views

What advantage would someone gain by installing my root certificate?

The answer to this is probably simple, but it eludes me. Here's the scenario: At the moment, I have a server with a certificate issued to it using HTTPS that a customer POSTs responses to after ...
1
vote
2answers
25 views

Mandadory checks a client should make to verify a ssl/tls certificate [duplicate]

Let's say I have a client, not a browser, that wants to connect with https to a server. It could be a python program, an android app or a library etc. Suppose the client has a list of trusted CAs and ...
31
votes
2answers
2k views

Can a SSL certificate have longer validity period than its parent in X.509 chain?

When a X.509 certificate chain is composed of X1, X2 ... Xn and Xn is root CA, Can a certificate in lower level have longer validity period than its parents? I think that lower level should be proper ...
1
vote
1answer
44 views

How to determine effective trust chain for cert on MacOS X?

I'm seeing some curious issues with cert verification for an Issuer: Entrust - L1K cert that was issued and is in use (per inspection of the cert in Chrome and Firefox) for an internal site here. I ...
3
votes
1answer
39 views

What security impact is caused by a TLS server continuing the handshake when presented with an invalid SNI?

RFC 6066 defines Server Name Indication as an extension, whereby virtualised web servers may be given an SNI extension in order to know which certificate should be presented. It has the following to ...
4
votes
1answer
104 views

Prevent and/or detect installation of root certificates on Windows?

I noticed that some applications installed root certificates on my computer. Is it possible to prevent this? Or is there a firewall or such that notifies me?
1
vote
0answers
27 views

OCSP recording with JMeter

How can I record an application which is using OCSP security with the help of JMeter? I am not able to record the application i.e. a native app with the help of JMeter as it is using OCSP protocol ...
1
vote
0answers
27 views

How to provide our customers ability to self service client certificate creation?

We have an API for B2B customers to access our platform. We require each B2B customer to have a client certificate. This is not the URL SSL certificate (https). The CN of each customer's client ...
1
vote
0answers
30 views

What comes into calculation of certificate signature?

I have written my own code with openssl in order to create certificates. In order to verify this code, I tried to reconstruct an openssl commandline generated self-signed certificate ... openssl req ...
1
vote
1answer
52 views

Can I move my private-key to a better token?

I recently purchased a personal signing certificate from GlobalSign - it wasn't cheap either. It arrived yesterday. GlobalSign gave me a "blank" USB security token device - a SafeNet eToken 5100. ...
2
votes
0answers
29 views

Disadvantages of self signed and cross signed certificates? [closed]

Can anyone explain what are the disadvantages or loopholes in self signed and cross signed certificates?
7
votes
2answers
430 views

Are any major websites offering ECDSA authentication?

At the time the Cloudflare blog post “ECDSA: The digital signature algorithm of a better internet” was authored, Cloudflare was apparently one of "fewer than fifty" users of ECDSA certificates on the ...