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23

This message is Google trying to push people nilly-willy into the 21st century of cryptography. So they point and mock when they see "RC4" or "SHA-1". This does not mean that such algorithms can be broken immediately. Only that Google would find the world a better place (or possibly a googler place) if everybody were using algorithms more to their liking, ...


22

Certificates are signed and the cryptographic signature is verified; if the signature matches then the certificate contents are exactly as they were when the certificate was signed. This, of course, does not solve the problem, it merely moves it around. The complete structure is called a PKI. The certificates which are preinstalled in your computer (came ...


14

There is nothing at all wrong with running your own internal certificate authority; the vast majority of large companies that I have interacted with have their own internal CA. Advantages The nominal cost of a cert becomes nearly zero when amortized over enough systems and users; when you purchase certificates from an external CA, this will never become ...


6

If a virus installs a new root certificate on your computer, and a spoofed website presents you with a certificate with a valid signature chain from that root certificate, then your computer will accept it as a valid certificate. But this shouldn't be seen as a problem with SSL/TLS -- if you have a virus with that level of access, then there are lots of ways ...


4

The following is a possible series of steps you could take. I'm considering that you have a secondary, online HSM for the period during which the affected HSM is removed from service for repair. Destroy all key material on the HSM Notify vendor of device problem and serial number Return device in tamper evident packaging to vendor address using secure ...


4

I would assume that the test/dev environment is more 'open' than Prod, in terms of who can access it with admin privileges, etc. If this is the case, and e.g. the dev team and/or external resources have access to the additional environment then that potentially increases the risk that the private key is compromized. If this is a concern, I would splurge out ...


3

SSL certificates provide two things: Authentication of the organization to whom the visitor is connecting (the organization is verified to be www.foobar.com) Confidentiality of the communication (data is encrypted using the public keys in the certificate) Concerning point 2, there's no difference in using a self-signed cert, a certificate issued from a ...


3

Short answer: No. I think you won't be happy with only three CAs. Lots of clicking around certificate warnings. This will not make your browsing safer. Also reconsider what you are trying to achieve. I'm assuming, that you want to protect yourself from rogue and/or exploited CAs. So that means CAs that will issue certificates for google.com, etc, when ...


2

RFC 5280 section 4.1.1.3 talks about the scope of the signature 4.1.1.3. signatureValue The signatureValue field contains a digital signature computed upon the ASN.1 DER encoded tbsCertificate. The ASN.1 DER encoded tbsCertificate is used as the input to the signature function. This signature value is encoded as a BIT STRING and included in ...


2

Actually you do not modify the certificate itself. As explained here, the pfx file is container containing the certificate plus several other objects, including the certificate. What you do in the given procedure is get the certificate out of this container, then put it in another container associated to different objects. The certificate itself remains ...


2

Some things to consider when dealing with TLS as a protocol. The payload of the communicating packet is encrypted. The 'dst' & 'src' packet attributes are not, which allows for any device within the network route to intercept your communication. Numerous attack against the SSL & TLS protocol over the years have allowed for the following attack ...


2

These sites set the HSTS header (HTTP Strict Transport Security). If you have visited these site without the Burp proxy before, your browser knows (cached) the HSTS policy and sees a mismatch. The HSTS Policy specifies a period of time during which the user shall access the server in a secure-only fashion. HTTP Strict Transport Security (HSTS) is a web ...


2

You can see the client-side certificate as a key. Wherever the key is installed, the client will be able to connect. At the opposite, wherever the key is not installed, the client will not be able to connect. However, bear in mind that the client-side certificate is actually just a file a browser can import. It is not something hard-linked to a physical ...


2

The problem isn't your certificate, it's the certificate of googleapis.com, which you're accessing by way of loading their jQuery libraries. If you go directly to one of the scripts, you can click on the padlock icon and see more information about the SSL certificate: +- GeoTrust Global CA +--- Google Internet Authority G2 +----- *.storage.googleapis.com ...


2

The error message is just misleading You said yourself: I know that AES_256_CBC isn't considered modern cryptography, so the warning about obsolete cryptography would still appear. And that is why you get that message. Now unfortunately the message itself is not very clearly phrased. SHA-1 is used in several circumstances. And here the "SHA-1" ...


1

Your certificate may use SHA-256, however you still have SHA-1 cipher suites enabled: TLS_DHE_RSA_WITH_AES_256_CBC_SHA TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA TLS_DHE_RSA_WITH_AES_128_CBC_SHA TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA Disable these and the warning should go away. Edit in response to comment: The Chrome cipher suites are as follows: ...


1

Your certificate must be identified at least using his Common Name (CN), or at best using his Distinguished Name (DN). The Distinguished Name is based upon X.500 directory service standard, and is actually a hierarchical set of property/value couples allowing a unique identification of a given certificate, independently of technical certificate properties ...


1

With standard browser, it will most likely not work. However, nothing prevents such behavior with standalone applications (see Thomas Pornin's answer to SSL root certificate optional?), in such case one would talk of a trust anchor, ie. it is not a root certificate (it is not self-signed) but is nevertheless a trusted certificate usable as starting point to ...


1

I believe your understanding is correct. I think Windows stores intermediates because: 1) Having local copies of intermediate certs allows it to "cope" with connection scenarios where the remote server is not chained properly. I've seen scenarios where a web server isn't configured properly but IE doesn't complain. 2) The certificates are used for other ...


1

There is no real difference between machine and user certificates: it's a X509 cert that is used during the TLS handshake as client authentication (client authenticated handshake). The difference is how the certificate is installed and configured on the client: typically, a user certificate will be linked to the user account. depending on the system, it ...


1

Large edits because now it is clear that OP is asking about devices which only work as a TLS client... If this is only for client devices than you don't need to update the certificate on the device since there is no certificate on the device. The certificate is on the server (which you need to update) and is checked against the root-CA on the client device. ...


1

Yes, it is possible for X.509 to be only "TLS client" (actually to have the extended key usage only set to client). I suggest you to take a look at XCA, it is free a graphical tool which will allow to easily create and manage certificates (it is actually a small PKI). You will then be able to visually see all the main options a certificate can have, which ...


1

The public and private key have the same size (with regards to security, the file size differs of course). It's identical to the size of the modulus when it is regarded as an unsigned integer (and the key size is a full number of bytes, i.e. a multiple of 8 - otherwise it is the location of the highest bit set to one). You are however showing a full X509 ...


1

While thinking about it, I can now definitively answer that some CA offers Web API allowing to automate part or all of the certificate generation / signature. Some concrete example of this are Digicert, GlobalSign, Gandi. Some other CA may therefore offer the same services, however you need to check: The available functionality, not all functions ...


1

Note that EV certs are not structurally different -- they are just a cert issued under a different policy. So you have to check the policy. See http://en.wikipedia.org/wiki/Extended_Validation_Certificate#Extended_Validation_certificate_identification You will need to do a fairly extensive table lookup, won't be native to openssl I'm afraid. This is ...


1

Goodness. No it is not safe to send the CSR by email. The comments above regarding the lack of any secrets in the CSR are fine but they miss the point. A certificate authority, by signing a CSR and thus issuing a certificate, is stating that the contents of the CSR are true. As email is an insecure transport then there is no guarantee per se that the CSR ...


1

It may depend on how your certificate is installed. If your client doesn't recognize your certificate, then there's your problem. Go read up on how certificates work to understand what's happening here. If your certificate is installed as a globally-trusted root CA, then the browser will assume that a public CA is behaving badly again, and won't let the ...



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