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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881 views

openssl ECDHE-RSA… cipher suite selected while using RSA server cert and ECDSA client cert

The scene: s_server using RSA certificate. s_client using ECC-ECDSA certificate. Client authentication is required (option -Verify set on s_server) Cipher-suite selected after handshake is ...
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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 ...
2
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1answer
85 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 ...
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0answers
42 views

Signed an executable; appears as unsigned on VMs?

I signed my binary with a certificate issued by GoDaddy. It seems that myself and everyone I could get to test it for me confirms that it is indeed signed (much like signtool verify) However, when I ...
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0answers
58 views

What certificate attributes can I check to verify if an issuer is correct?

Apologies if this is a duplicate question. I thought I saw this discussed earlier but couldn't find the thread when searching. What attribute can I check to verify if I have the correct ...
4
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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 ...
6
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1answer
234 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 ...
13
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3answers
1k views

Trying to understand why signatures in root certs “are not used”?

Taken from here: Don't worry if the root certificate uses SHA1; signatures on roots are not used (and Chrome won't warn about them. Why are the signatures not used? Are not root certificates ...
3
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2answers
274 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 ...
17
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3answers
3k views

Is SHA1 weak for SSL?

I noticed that today after I scanned a site on the Qualys SSL Labs site that SSL ciphersuites which use SHA1 are now highlighted as being "Weak". It seems this has just happened; I scan sites pretty ...
1
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1answer
75 views

Does the SSL/TLS client certificate “hash over all previous messages” step hash the entire TCP packets or just data?

We have which uses TLS client certificates as it's authentication mechanism between client and server. There is an IT department which wants to run this app through a firewall/proxy device of some ...
5
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2answers
2k views

Are certificate authorities required to obey to the signature algorithm (hashing) specified in the CSR?

I was playing a little bit with signature algorithms, trying to determine which CAs among the ones I use are currently issuing SHA2 certificates. I generated a CSR specifying the SHA256 hash (either ...
1
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1answer
136 views

What is stopping me from replaying an SSL certificate?

Say I have the SSL certificate for google.com. I intercept it, edit the certificate with my own domain name and public key and use it to intercept all traffic to google.com. What mechanisms exist in ...
0
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1answer
78 views

Secure way to pass client certificate to the client2

Our product is comprised of two servers. We would like to authenticate one server to the main server by means of client certificate. I assume that we should ask the customers (who purchase the ...
26
votes
3answers
2k views

Is there a security issue in using the same certificate for all a company's services?

We are a small startup. One of our products is a B2B web service, accessible through its https://service.example.com canonical URL. For testing purposes, that service also runs on different ...
0
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0answers
24 views

Installer digital signature timestamp inconsistency

I just noticed that the digital signature on an old installer EXE is expired (it's LibreOffice from May 2013, and I'm pretty sure it was valid when I installed it). Investigating further, the time ...
1
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2answers
82 views

How secure are SSL client certificate authentications? [duplicate]

As far as I understand it's possible to issue SSL certificates, which could be used by clients for authentication. So in theory only users with valid certificates would be able to access a certain web ...
0
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2answers
308 views

Problem with OpenSSL rejecting CA possibly due to 12 digit Serial No

I work as a tester at a VoIP software company. We've been running into a problem with using TLS to communicate with certain phones. The phones are from different manufacturers but both exhibit the ...
23
votes
9answers
5k views

Can an HTTPS site be malicious or unsafe?

I know it's possible for a computer to be infected just by visiting a website. I also know that HTTPS websites are secure. To my understanding, "secure" here refers to "immune to MITM attacks", but ...
0
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2answers
82 views

Why do certificate authorities often require/use multiple intermediates?

I suppose this is related to What is an intermediate certificate authority? but I think my question is a bit different so I'll ask it anyway. Why do most modern certificate authorities (e.g. ...
0
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0answers
24 views

Certificate Errors on Network and Desktop Icons Freeze

What causes a screen on all devices on the same network to temporarily lock up and display certificate errors? After accessing Facebook; I have received a certificate error on both the student laptop ...
5
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3answers
4k views

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: ...
-1
votes
1answer
105 views

VPN security/compromise

I want to get a VPN with one of the known providers. I don't know much about VPNs but I know they issue certificates which you download and it authenticates the connection and basically gives access. ...
0
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0answers
86 views

Problems implementing Authority Information Access in a certificate

I am implementing SSL certificates for internal use in an application. Due to the nature of this app, I'm basically implementing my own CA. I have created a self-signed cert for the CA to issue ...
2
votes
2answers
87 views

Should expired compromised certificates be taken care of if the time is always correct?

I am trying to set up a CA for my company, and issuing every employee a digital certificate and a private key. I am worrying about revocation and expiration. In my case, the root certificate of CA is ...
1
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1answer
276 views

Why OpenVPN is using both certificates and DH?

I am reading about OPENVPN and I am a little bit confused. In the OPENVPN howto website, there is a step by step setup guide for generating certificates and diffie-hellman (DH) params. However, I cant ...
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2answers
248 views

ECDSA ciphers and forward secrecy question about key exchange

I have heard that with forward secrecy that the ECDSA ciphers generate different keys for "each session" because they are not dependent on the private key of the server. My question is how is "each ...
2
votes
1answer
49 views

Possibility of using CA as an attack point by governmental organizations under their pressure

I was always concerned about the model of trust behind CA stuff we use . Well, for most of us, it is OK to trust them, since they are reliable organizations with a bunch of solid experience. ...
3
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3answers
1k views

Free second-level domain SSL certificate [closed]

With CAcert.org losing trust in browsers and OSs and StartSSL providing only top-level domain certificates, are there any free SSL certificates providers for second-level domains?
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 ...
9
votes
1answer
219 views

How should I store and secure self-signed certificates?

I'm fairly certain I shouldn't commit certificates into source control. Even if the repository is private and only authenticated coworkers (for example) have access to it. That would allow for ...
3
votes
2answers
578 views

What is the difference between EV-SSL certificates and Normal SSL certificates? [duplicate]

Recently while looking at several banking URLs I can see the domain name with security certificate at address bar and normal locker security certificate at address bar. Have a look at the screenshots: ...
2
votes
1answer
162 views

ECDSA/RSA certifcates and cipher selection

In this image can someone tell me if a standard RSA certificate can support the EC*_RSA ciphers listed? If so do you create the typical RSA keys when you are creating the CSR? Also I am fairly ...
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2answers
4k views

This certificate has an invalid digital signature

I am trying to learn securing wcf service using ssl. I found this website and I am following the steps. ...
2
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1answer
3k views

What is the deal with Valicert SSL root certificates?

Does anyone know what the status of the "Valicert Class 2 Validation Authority" root certificate is or what's going on with Valicert in general? I've heard that that cert has been deprecated, no ...
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votes
1answer
33 views

Choosing right way to secure access to server access via socket

I have an application running on a server, that has an exposed socket to the Internet to communicate with client that is/are application(s) on a phone. How would one go about properly securing the ...
2
votes
4answers
2k views

SSL root certificate optional?

I may have been under the wrong impression on how servers should be setup and what certificates actually get sent over during the server hello certificate message. I came across this today from ...
3
votes
2answers
175 views

How does iOS prevent unauthorised code from running?

I'm just wondering. How does iOS prevent someone from executing code on their device that isn't from Apple or downloaded from the App Store? Also what exactly, does a Jailbreak do to allow ...
3
votes
2answers
380 views

Why is a CSR hashed?

What are the use cases for defining something other than the default SHA1 hash in a CSR? Is it to protect the digital signature, public/private keys? What is it protecting exactly?
4
votes
1answer
18k views

Can a CSR be created in OpenSSL with SHA2?

Can a CSR be created in OpenSSL with SHA2? If so, what would the command be and what does this tell the CA, if anything? If you could create a CSR using SHA2 would it "tell" the signing CA to use it ...
1
vote
1answer
103 views

Would it be possible to use cookie to store SSL Client Certificate?

Lately, I was reading that article about SSL client certificate. Why is nobody using SSL Client Certificate? The answer was to that question was : In the current state, this excellent idea is ...
3
votes
2answers
1k views

How to simulate man in the middle attack in android emulator?

I am new to pen-testing. Yesterday i analysed one android application using dex2jar application and i saw an android application implemented https connection using empty trust manager. class miTM ...
6
votes
1answer
5k views

4096 bit RSA encryption keys vs 2048

Where do 4096 bit RSA keys for SSL certs currently stand in terms of things like CA support, browser support, etc? In the overall scheme of things is the increased security worth the risk of 4096 bit ...
1
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2answers
97 views

Is it Possible to use one commercial SSL Certificate to issue end user certs?

My organization is preparing to purchase some 50 "units" from Symantec, with which we can purchase Verisign SSL certificates of varying authentication levels. Our organization does not have--but ...
0
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2answers
131 views

Typical mistakes when implementing digital signatures?

I am looking for a list of typical mistakes someone can make when implementing digital signatures for a software. And of course why they are mistakes and how an attacker could take advantage of them. ...
2
votes
1answer
220 views

Self-signing client certificates and distributing them, is the following a sound procedure?

I have a case at hand as follows: There is a number of clients in Internet (i.e. untrusted channel), initially in hundreds but growing in numbers. There is a server doing processing related to these ...
-1
votes
2answers
173 views

Installing self-made cert as trusted CA on windows?

I'm looking into using mitm-proxy, but part of the process of filtering/snooping SSL is that you must generate and install a root cert as a trusted CA, so that mitm-proxy can generate and throw out ...
1
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2answers
81 views

SSL for only parts of a website… How does it work?

I understand that CAs issue certificates based on common names (CNs) like www.amazon.com and that certs are not based on URLs like www.amazon.com/stuff. How is it that when I go to www.amazon.com, it ...
1
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0answers
241 views

If even Apple cannot properly install certificate [closed]

I've just installed a new copy of Mozilla Firefox/29.0 SeaMonkey/2.26.1 on a new Mac with OS X 10.9.4, and I'm getting an error message in place of a webpage when trying to access ...
0
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1answer
201 views

Reverse proxy sharing one certificate for multiple servers using Subject Alternative Name

The following is a scenario for an attack where one website can impersonate another. I am told (including by this answer) that it's impossible, but I would like to understand exactly what prevents it. ...