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5

HSTS only forces a site to use HTTPS. This prevents downgrade attacks such as SSLstrip from being effective. As HSTS says nothing about the certificate that will be used, it has no effect when you renew your certificate. HTTP public key pinning, a related technology, is used to force a browser to only allow a site to be visited with a certificate using a ...


0

Look at RFC 5246 Section 6.3. On both sides, bytes are generated using the PRF from the same arguments, so the generated bytes are the same. Those generated bytes are used the following way: The first "mac_key_length" bytes (e.g. 20 bytes) are the client's MAC key and the next "mac_key_length" are the server's. Then the next "enc_key_length" (e.g. 16 bytes) ...


4

TL;TR: there is maybe (or maybe not) some substance to the patent but I consider the claims made in the press widely exaggerated. I don't see any substance for the claims of helping against MITM. And it addresses different use cases than TLS, so no need to compare. While there was lots of press end of 2014 about this issue it basically repeats the same ...


3

When the connection is insecure, the strike through is supposed to be solid line over the https scheme name: https://support.mozilla.org/en-US/kb/how-do-i-tell-if-my-connection-is-secure That yours show up as broken lines is probably a graphical glitch.


3

... how it proves anything about my identity to the webserver? It does not. It only proves the identity of the server to you so that a man in the middle attack (where someone claims to be google.com) is not possible. If client identification is required (usually not) client certificates could be used. "The certificate is intended... Proves your ...


0

To see which cipher suites are used by the browsers have a look at the client tests at SSLLabs (you need to look at the details for each browser). But it might be better to simply use known good configurations like the recommended configurations from Mozilla.


0

AFAIK setting the exception in each users browser is the only way to get rid of that message when using a self-signed certificate. But: If your company has a wildcard certificate you could define a sub domain, that is just accessible in local net. If your company doesn't have the wildcard certificate, you could still create the sub-domain, acquire a free ...


1

NGiNX SSL Session ID available in $ssl_session_id variable. Other NGiNX SSL variables can be found here, Embedded Variables section.


0

There's nothing to say that this HTTP response header should be sent for HTML content types only. As long as the header has a good chance of being received by the browser over HTTPS at the start of each session, then the policy will be adhered to until expiry (max-age), if not renewed by another response.


0

The important question here is wheater you trust your company or not. If your company isn't trustworthy they could easily steal your password without a certificate (e.g. by using a key-logger). If your company is trustworthy the fact that they have installed a certificate on your system doesn't matter, since you trust them anyway. Should the fact that ...


1

Since the policy of HSTS gets applied to the whole site it is enough that you sent it together with a resource which is definitely read by the client. This can be a HTML page, it can be an image, ... as long as the client will definitely request this resource so that it knows the policy.


4

Changes to DNS aliases (CNAME) or IP addresses do not matter at all to certificate validation. All what matters is that the hostname as seen by the client (for example the name in the URL) matches the subject(s) of the certificate. This name will not change on any changes to the DNS. Often a DNS CNAME gets confused with a HTTP redirect. In the case of CNAME ...


1

The most logical solution is to place the name in the subject of the certificate, and use dynamic DNS to make the name point to the same raspberry PI. Of course, one would need a DNS server. If you can use IPv6 and having a DNS server is too much work, with it the Rasbperry would have a fixed address automatically with stateless autoconfiguration (based on ...


3

Why not register the certificate for a fully-qualified domain name, instead of for the IP address? Assuming you're running it as a server, and leave it running for good stretches of time, you'd visit the DNS provider, and change the mapping between IP address and domain name, only when you received a new IP address. Additionally you could request a static ...


0

I don't think the old ciphersuites are too much of a worry in themselves as your server should not ever negotiate them. What is more of a worry is that they indicate that the SSL/TLS stack in the client in general is very old. In general with ssl/tls the client authenticates the server but the server does not authenticate the client at a tls level, (higher ...


2

It depends on the application but usually, that is no problem if you have root on the system Check what Host name the application uses, create a cert for that name, add it to the machine or application trusted root store and redirect Host name to a proxy server you control. After that, either configure the proxy to dump the clear text content of the ...


4

Given how old these ciphers are I could imagine that the client also supports SSLv2 which is broken. Also it will probably accept certificates signed with MD5 or even MD4 or MD2 which are broken too so one should be able to create a faked certificate accepted by the client. That is if the client checks certificates at all because even a few years ago it was ...


0

The whole point of using HTTPS is that it prevents such attacks that break the integrity of the connection. You would need to do an SSL MiTM and break the SSL. However breaking SSL will mean that the user's browser will prompt the user about this break in SSL, and you would need to be dependent on the user ignoring such errors. Also keep in mind that it is ...


2

For sites like google and facebook several browser have preloaded HSTS (enforce HTTPS) and HPKP (certificate/public key pinning) settings. This means that the browser knows that these sites should be reachable by https only and how the certificate should look like. And this means that stripping SSL and the HSTS header (i.e. your --hsts option) will not work ...


0

Here are some reasons that sites do not implement forward secrecy (also called Perfect Forward Secrecy or PFS). By definition, only the TLS-terminating server and the client can decrypt the actual payload. This means that other processes, which may have a legitimate reason to decrypt the cipher text, are locked out of the conversation. There are many ...


0

Try Network Miner Run the PCAP file through Network Miner. It extracts certs and other file types.


2

With new versions of wireshark: Make sure the traffic is decoded as SSL, i.e. setup the SSL analyzer for this TCP stream in Analyze >> Decode As. Now it will show the SSL details for the packets. Pick the packet which contains the certificate, in this case packet 6. In the packet details expand Secure Socket Layer etc until you get to the certificate ...


0

Natively, through Wireshark: How to obtain the SSL certificate from a Wireshark packet capture: From the Wireshark menu choose Edit > Preferences and ensure that “Allow subdissector to reassemble TCP streams” is ticked in the TCP protocol preferences Find “Certificate, Server Hello” (or Client Hello if it is a client-side certificate that you ...


7

I am currently running my website in shared hosting, and I am not able to register TLS/SSL for my website. There is no reasonable alternative to TLS, and trying to re-create it on your own is certainly doomed. Never roll your own crypto. If your shared host doesn't support TLS, then find one that does, or else accept that your site is insecure. ...


1

Also if you just want to see the application level traffic, use a proxy like burp suite . Configure the proxy on your smartphone and then you can see all the application level traffic on burp suite running on your system .


1

should I be able to read that devices incoming & outgoing ssl/tls traffic, in an unencrypted/decrypted state? In general TLS happens inside the application or libraries. By the time the traffic gets to wireshark it's already encrypted. To view the content you need to decrypt it and TLS is designed to make that difficult. If the server uses a ...


1

You need the private key of the server and then you can feed it into wireshark. Also to capture from smartphone, set up a file sharing network. I kind of did it with Windows 7 but not sure about exact steps. Google it, you will find the details.


2

don't know about the smartphone case, but with Wireshark, as long as you own the key you can. Here you have a video doing all the walkthrough and here a Wireshark wiki post about it. Basically you need to go to the preferences of the SSL protocol and put the key file.


0

No, there is only one public key in the certificate. Obviously the server should also have the private key that belongs to the public key in the certificate. The session key is retrieved using key establishment. There are basically two ways: the master secret is generated and then encrypted by the client using the public key of the server, the server can ...


0

The most up to date answer can be found in Apple's Enterprise iOS Deployment Reference: http://help.apple.com/deployment/ios/#/apda0e3426d7 See: Certificate validation The first time a user opens an app, the distribution certificate is validated by contacting Apple’s OCSP server. If the certificate has been revoked, the app won’t launch. To verify the ...


1

To begin with - I won't go into too much detail for this answer. Read more about HTTPS and the certificate system if you're curious ;-) HTTPS needs certificates to work. These certificates are meant to be a guarantee that you're talking to the right server (and not to the server of an intruder). Encryption only (without this authentication) would be ...


0

Use some one else's PEM bundle. You can not use the Windows certificate store directly with OpenSSL. OpenSSL expects its CAs in one of two ways: In a special folder structure. One file per certificate with regular names like "Verisign-CA.pem". (This is so that humans can understand the cert store.) And then a symlink to each such file. And the symlinks ...


4

No, it is not possible to determine the state of SSL pinning at the client. SSL pinning is part of the certificate validation done solely inside the client and the only feedback the server gets is if the validation succeeded (connection continues) or not (connection closed, maybe TLS alert). Also there is nothing fully reliable the server could to to "ask" ...


0

The security is security, no matter the network zone. Yes, there are not so much potential attacckers for LAN-only server, but it's not just leveraged, but hightened by the network speed : one lan attacker on strong/stable/guaranteed 1Gbps speed can try as many passwords, as 100 attackers from the WAN/WWW/Web with unstable connection speed, for example. Use ...


0

Hard to say. The most common cause for SSL/TLS handshake failure is an inability to agree upon a common protocol and cipher. Because the protocol/cipher suite presented by the client is going to vary widely from client to client, and the suite supported by the server is going to vary widely from server to server, there's no way to do a real statistical ...


1

Short answer: No, not everyone can send a modified certificate to the client. Every certificate is digitally signed and the clients check these signatures. So you either need to ... create a fake signature (which is cryptographically hard), get a certificate autority to sign your certificate (which they should refuse to, because you are not owner of ...


4

Yes, the VPN provider is able to see your data. If the data are not encrypted (i.e. HTTPS) the provider will be able to get to the clear text and will also be able to manipulate the data. The usual protections of HTTPS apply, i.e. the provider will see which site you visit but not the clear text data itself because they are encrypted. The provider will also ...


0

If you are in hurry. Let me give you my personal opinion. Just understand the following words which I am going to list.. 1.data authenticity 2.data integrity 3.data encryption Common in all security protocols ipsec,SSL,any kind of security. How to provide these all using openssl 1.related words regarding to data authentication and integrity,encryption. ...


0

This book - https://www.feistyduck.com/books/bulletproof-ssl-and-tls/ by Ivan Ristić is best in the market for answering your question. I have read both mentioned books here. But, this book is a gem. It will teach you all the basics with negligible mathematics. It will properly give you recommendation on how to correctly deploy ssl/tls server using openssl. ...


1

From my understanding your problem is that an active man in the middle can make a server S access a URL at host U and this URL is specified by the attacker. And the problem with this is not that the attacker might get to the contents behind this URL (he can't) but that just accessing this URL might trigger a bug at the server U. Thus to make this attack ...


1

Thanks to the responses I was able to get it working. Here is some Python pseudo-code which explains the algorithm actually used by TLS 1.2: # Come up with a random premaster_secret # It needs to start with the TLS version (0x0303) premaster_secret = '\x03\x03' + os.urandom(46) # Retrieve the RSA parameters from the certificate public key RSA_n = ... RSA_e ...


1

In general, certificates are meant to be public. The idea of a certificate containing secret information doesn't really make sense. That being said, the certificate does contain information about the topology of your intranet (domain names of the servers, CN of your internal CA, etc). Maybe this gives attackers an advantage, maybe it doesn't. If your ...


4

Those is publicly available information. They are contained in the certificate and you "leak" them to all clients. What exactly are you concerned about? Your certificate is meant to be public. Edit for the edited question: Yes, those things can make the life of an attacker easier. the CN can leak the naming scheme for the network the CA can leak ...


2

Heartbleed exposes, as the other answer mentioned, arbitrary memory. On an unused NAS, this is most likely not sensitive information. Yet, this seems to be a certificate - maybe also, as polynomial said, (part of) the private key. Executing the exploit several times will probably yield different outputs; putting the pieces together can in fact yield ...


0

As far as I know, Whatsapp uses Certificate Pinning. When I tried to analyze the Android app in january, it didn't accept my forged certificates (created with mitmproxy). I didn't invesigate this further and I might have missed something. However, Whatsapp upgraded its encryption algorithms earlier this year and introduced end-to-end encryption, and ...


4

Heartbleed results in arbitrary server memory being disclosed. Sometimes this contains sensitive information. In some cases, this is the server's private key, which can be the most sensitive information on the server. In many cases, it can contain information that is intended for a different client. This is probably what you are seeing: certificates, version ...


3

You are correct to be concerned about the scenarios you presented: If a MITM attack occurs, it cannot be thwarted unless you use SSL. The IP filter will not help because the attack is already "in the middle" of the connection, so all traffic will pass through it in plain text. Once the user/pass is grabbed, the attacker can do whatever those credentials ...


1

You got the wrong certificate. Check the graph at the Let's encrypt site and you will see that a leaf certificate is not signed by the X1 certificate you've downloaded but by X3. If you would look at the certificate details (with openssl x509 -text or similar) you would also see the issuer of your certificate and you could check that it matches the subject ...


4

If you look at the MySQL Internals Documentation, you can see that the protocol initialises SSL/TLS after the initial handshake packet, but before the authentication step:   The two paths shown from the first state are based on whether SSL/TLS is enabled or not. As such, if SSL/TLS is enabled, the authentication occurs after the secure channel is ...


0

To play MITM with HTTPS, your ISP would need to create fake server certificates on the fly for the domains you visit. Your browser would flag these certificates as security probems, since they would not be signed by any trusted CA. That is, unless you imported the CA certificate used by the ISP as a trusted CA. In that case your browser will think everything ...



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