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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27 views

Why do some unrelated websites (appear to) share certificates? [duplicate]

If you browse to https://blog.stackoverflow.com/ you see a certificate error. In Chrome: This server could not prove that it is blog.stackoverflow.com; its security certificate is from ...
2
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2answers
122 views

PKI certificate validation graphs, trees and cross signing

I am just trying to get the basics of PKI and TLS and understand how it works. I came across Mozillas post about pkix where they mention that the new library allows graph processing and hence it ...
0
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2answers
146 views

How to be sure that downloaded file is correct? [duplicate]

Last week I read a lot about security. I have a basic understanding how public keys or private keys works. But I still have a lot of questions I can't find an answer. Right now I'm interested in ...
2
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2answers
200 views

Certificate authorities: history and registration

CA's are a key part of the internet's infrastructure few people are aware of. SSL was mostly hacked together at Netscape in 1995. I'd like to understand more about the organizational structure of CA's ...
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1answer
141 views

Machine Certificate Key File Artifacts

When a new machine certificate is imported with a private key a MachineKey file is generated in "%ProgramData%\Microsoft\Crypto\RSA\MachineKeys". When using the certificate mmc snapin or removing a ...
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2answers
703 views

Intercepting SSL traffic on Android app

I am trying to intercept SSL traffic from my Android app to test the security. I am using certificate pinning in the hopes I can prevent people from snooping. I have tested by configuring ProxyDroid ...
0
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1answer
316 views

Mac OS X : Certificates signed by company trusted CA cannot be verified

I'm trying to setup a keychain on Apache Tomcat that contains a server certificate that was signed by a custom root ca certificate. (not sure if custom is the right word here, but it's a root ...
3
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2answers
571 views

Validating an SSL certificate chain according to RFC 5280: Am I understanding this correctly?

we're in the process of replacing certificates with SHA1 hash due to Google's move to let them appear less secure in Chrome. The replacement certificates use a different intermediate CA than the ones ...
0
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1answer
128 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 ...
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2answers
124 views

SSL Certificate Trust Model

I have been looking at the SSL Certificate Trust Model, and there is something that does not make sense. If I am correct, the trust model makes it that if there is a chain of certificates with a ...
3
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1answer
65 views

Clarification on the -h Flag for Makecert.exe

When using Microsoft's Makecert.exe to generate a certificate (and key), there is the option to allegedly "specify the maximum height of the tree below that certificate", using the -h flag (see MSDN). ...
5
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1answer
3k views

ECDHE_RSA and gmail

I'm using Chrome on Ubuntu Linux to connect to Gmail. The connection info says that ECDHE_RSA is used for the https symmetric key exchange. Based on my understanding of TLS and Gmail, my client ...
8
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4answers
911 views

How bad it is to install another company's root certificate to your server?

Our company uses a web server with a couple of web sites on it (private and public, over HTTP and HTTPS, some low risk and some high risk including online payments or other sensitive data for ...
0
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1answer
295 views

Isn't this a broken certificate chain?

My certificate provider responded to my CSR with four certificates, the first being "ours", and the remaining three presumably to build a chain of trust. I've never had to investigate (and prove to ...
0
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1answer
38 views

Can an end-entity certificate with SHA-1 be issued by an intermediate CA that has SHA-256?

Just curious - if I'm using an end-entity (leaf) certificate that has a SHA-1 signature, does that mean that ALL certificates in the chain also must use SHA-1?
3
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2answers
270 views

What role do hashes play in TLS/SSL certificate validation?

After coming across this question in the Hot Network Questions section and reading the related blog post by Google, I'm starting to become curious as to what role these hash functions play in TLS/SSL ...
6
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1answer
2k views

Reset Windows trusted certificates store to its default

Over the time I have installed several additional trusted CA certificates to Windows trust store, sometimes because an app pushed me to do so, some other times for development and testing. Is there ...
2
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1answer
1k views

What is the difference between a “Thumbprint Algorithm” “Signature Algorithm” and “Signature Hash Algorithm” for a certificates?

I'm a bit confused on the differences between Signature Algorithm, Signature Hash Algorithm, and Thumbprint Algorithm that are present in SSL/TLS certificates. Can someone please elaborate?
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6answers
4k views

How can I know that the CA certificates in my computer have not been spoofed?

As far as I know, the browser contains the certificates of several CA. When I access http://gmail.com, the site says it is Gmail, it exposes a certificate signed by one of the CA I have in my ...
0
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1answer
128 views

What would cause a server to only send over 1 SSL certificate to a client? [closed]

We have a secure server that seems to only be sending over the identity certificate. Running the hostname through Qualys says that only 1 cert was provided. The intermediate had to be downloaded on ...
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2answers
133 views

Uploading pfx certificate to Azure

In order to use SSL with a custom domain in Azure Websites you must upload a pfx file with your certificate and private key to Azure. What are the ramifications of trusting Azure with the private ...
11
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2answers
5k views

What are the advantages of EV Certificate?

What are the various advantages of using extended validation (EV) certificates than normal certificates which also provide comparatively high degree of encryption like RC4, 128 Bit? I know that the ...
-1
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1answer
58 views

How do server know the CSR sender is approved client?

Suppose have a server provide a POST url to send CSR. The response certificate then will be used for later SSL client-cert auth connection. The prblem is anyone can POST a CSR to the server and then ...
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2answers
78 views

PKI expired and renewed, do my correspondents have to do anything?

My PKI certificate (Digital ID for email from Symantec, issuer is "VeriSign Client External Certification Authority - G3") expired after 1 year and so I have renewed it. Do the people I correspond ...
0
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0answers
38 views

Do iOS applications have access to the certificates installed?

As the title says, I'm curious if a generic iOS application can access/retrieve the certificates installed in the device (e.g., via a management profile) Thanks
8
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4answers
764 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 ...
0
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1answer
66 views

What is public key pinning [closed]

How does public key pinning work and what problem does it solve?
2
votes
2answers
167 views

Why would Comodo SSL certs have two intermediate CAs (chain length 4)?

Comodo certs such as PositiveSSL have a chain length of 4, including two intermediate CA certs. What would be the benefit to them, or to me, of this length chain instead of a chain length of 3 with a ...
0
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1answer
509 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 ...
0
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0answers
52 views

Attack Vector for Wildcard Cert

So I am looking to the security risks of WildCard Certs, in a previous post most of the questions were answered however I have one follow up question for that. In my instance I use DigiCert, so ...
5
votes
2answers
869 views

Website Certificate Revocation check - Big deal? [duplicate]

As I was about to make payment for my flight ticket, I noticed something strange with the British Airways website's SSL cert. My browser (Google Chrome) was unable to check whether the certificate has ...
19
votes
3answers
9k views

What vulnerabilities could be caused by a wildcard SSL cert?

In a comment on this answer, AviD says: "There are numerous security issues with wildcard SSL certs." So, what are the problems? I understand that the same private key is being used in multiple ...
1
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1answer
217 views

Know certificate signing algorithm of a remote site using OpenSSL

I have been trying to know the "Certificate Signing Algorithm" ( SHA1 with RSA etc.) using openssl. To start with I tried to see the cerificate using following command, but it also does not show up ...
0
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1answer
2k views

Creating Client Certificates

Consider an application where client certificates are to be used for authentication. The application web server requires SSL and client certificates for all users. In this case, it's IIS 7. I've used ...
11
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4answers
1k views

Multiple CAs signing a single Cert/CSR?

Just saw this suggested on Slashdot So I've seen quite a few people wanting a switch to self-signed certs (who IMO mostly don't understand what making that secure actually involves), and an idea ...
0
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2answers
78 views

How are “Certificate Signing” key usage certificates restricted to what domains they can sign?

Many big websites use their own intermediate signing certificates to generate SSL certificates for their domains. The intermediate certificates are issued by the usual root CAs but have a "Certificate ...
4
votes
1answer
174 views

How will SHA1 deprecation affect internal CA's?

I am hearing that the SHA1 Deprecation notices from MS/CHROME only apply to certs that are a part of a public trusted root program. This makes one believe that IE will have new logic built in to allow ...
1
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1answer
57 views

SSL - Main and Child servers network

There is an embedded device which acts a client. It communicates to a server via POST method whenever it has any data to be transmitted to the server. Embedded device: 1. Acts a Client 2. Does not ...
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5answers
192 views

Are most MiTM attacks done to impersonate web sites, or simply decrypt traffic?

The more I read about impersonating web sites the more I get confused. Does an attacker need the private key of the server in order to impersonate a website or does having the private key simply give ...
2
votes
1answer
98 views

Does client certificate do any encryption in https connection? [duplicate]

In Https connection asymmetric encryption (with Server certificate) is used during handshake and to create symmetric keys. Am I right that in this case client certificate does no encryption? The ...
0
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2answers
352 views

Self-signed certificates and internal cURL requests

I'm using an internal API for some commercial software we purchased and it recommends using SSL when utilizing the API; it uses cURL to achieve this and hence the user, pass and key will all be passed ...
8
votes
4answers
1k views

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 ...
1
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1answer
304 views

Recommended Key Usage for a client certificate

My program has the following flow: a client sends a CSR to server, the server sends back a client certificate and after that the client communicate with the server to a path that requires a ...
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 ...
0
votes
1answer
196 views

Can anyone with access to root CA private key decrypt HTTPS traffic?

Can anyone with access to root CA private key decrypt HTTPS traffic of sites using certificate signed by that CA ? and if yes do he need to be man-in-the-middle or just monitoring traffic is ...
0
votes
1answer
184 views

Why are CA's now signing root certs with SHA2?

I see that CA's are now giving the option of having the root CA cert signed with SHA2. I have been told that the hashing function in a root has no security value, and is irrelevant as far as a ...
2
votes
2answers
184 views

Does a self-signed certificate offer more protection than a public key?

I'm having a hard time finding the practical benefits of transmitting a self-signed certificate over simply a public key. I understand that a self-signed certificate proves the integrity of the public ...
0
votes
2answers
213 views

What does 2^77.1 calls presented in a SHA1 attack mean?

Regarding the SHA 1 deprecation, I found this information here: http://blogs.technet.com/b/srd/archive/2013/11/12/security-advisory-2880823-recommendation-to-discontinue-use-of-sha-1.aspx I know ...
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1answer
235 views

Can't I forge an SSL certificate? [duplicate]

I read What's keeping a malicious man in the middle server from forging a valid certificate?, but when the client goes to verify the certificate, can't an attacker intercept that connection and say ...
6
votes
1answer
231 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 ...