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DPI threats against OpenVPN is pretty hard, unless the attacker somehow grabs the random, freshly generated session keys which is transmitted over an SSL connection. The SSL connection, in turn, is secured using a pre-shared certificate and a secret server certificate. So an attacker would need to compromise the server itself. Usually, said attackers would ...


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The classical DHE is computationally expensive, at least as these things go. This rarely matters (a normal PC can still do hundreds of DHE per second), but if you are in a situation where computing budget is tight (e.g. small embedded systems) then ECDHE is substantially cheaper. With "normal" implementations, the cost of DHE is proportional to p2r, where p ...


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In order to have high encryption strength, one would use large DH params (16k perhaps) since the classical DHE key exchange is not computationally expensive, I can't give you hard numbers for the speed. The openssl speed command does not seem to offer the benchmark for regular (finite field) Diffie-Hellman. This answer offers guidance on practical ...


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Server certificates can have multiple chain of trusts (the certificate have multiple roots), and the browser only need to trust one chain to trust the server's certificate. I don't know whether browser actually supports this for client certificates as well. But if they do, you would be able to ship the client certificate signed with two separate root ...


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On a side note you can use nmap with ssl-enum-ciphers script as follows nmap --script ssl-enum-ciphers -p 443 example.com You will get a response like this. PORT STATE SERVICE 443/tcp open https | ssl-enum-ciphers: | SSLv3: | ciphers: | TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA - strong | TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA - strong | ...


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Reading through this memo, a link is given to the un-pin draft of Perrin here. I see two countermeasures against the scenario which you describe in this draft: Let's start with the first one, which can be interpreted in different ways: Whenever a client performing "pin activation" sees a hostname and TSK combination not represented in the "pin ...


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These are simply Subdomains created by the website owner. ww3 is often used to share load (ww1,ww2,ww3) on their servers. In you example it seems intel created www-ssl subdomain to separate normal http traffic and https traffic on subdomain level. If you want more information why somebody is doing this, just ask google or the website owner


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I've checked All the websites You've mentioned using an online SHA Checker Tool - https://shachecker.com. As per the result none on this website found with the older SHA-1 algorithms. All seems okay with SHA-2 encryption. This problem might be from Google Chrome or from your MAC device.


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Yes it is true. When certificate is self-signed, then issuer and subject field contains the same value. Also, there will be only this one certificate in the certificate path.


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The server does not send any certificate in the ServerHello message; it sends certificates in the aptly-named Certificate message. As indicated in the standard, the server is supposed to send a complete, ordered chain of certificate, starting with the server's certificate proper, then a certificate for the intermediate CA that issued it, then a certificate ...


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Tldr This is what the little research I did was able to find. Most of these dates are as you can read in the longer version, based on the first submitted draft of the respective protocols and not the first time they've been talked about. I hope this might help in your work anyway, and that it might help when doing further research. SSLv1 - ...


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The IETF has a data tracker for its RFCs. This means that you can flesh out the development timeline by adding the various drafts for each RFC. And you can narrow down dates to the date of the first published draft. What this doesn't tell you when development for the first submitted draft of each RFC started. Also the "SSL" named protocols were not ...


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Is this a problem with my browser? Firefox 39 and the Firefox 31 and 38 ESR releases upgrade the TLS implementation NSS to version 3.19.1. To harden the browser against Logjam attack the minimum key length for DH parameter within the TLS handshake is now 1023 bits. But the server at acs.onlinesbi.com only uses a DH key of 768 bit. This key length is ...


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Instead of setting up multiple CAs, you can just tweak access settings in your Apache configuration. Look at Require directive: http://httpd.apache.org/docs/2.2/mod/core.html#require If you set any authentication requirement, then default Require level is implicitly set to "valid-user" (anyone that meets other requirements). But using Require, optionally ...


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As steffen points out there is a different between the public key and the cert fingerprint. The same public key can be reused in a new cert. A common example would be replacing a cert which is going to expire soon. The sad thing is symantec's own tool and website is at best misleading and at worst downright confusing. Symantec began having OSes and ...


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So are there actually two different legitimate versions of the VeriSign certificate which can be used to sign the same child certificate? Signing is done by the public key in the certificate. Both certificates have the same public key, so both can be used to verify the signature. The difference is that 18:da:d1:9e:26:7d:... is issued by itself while ...


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The process of establishing a full trust chain between two system using TLS is the following: 1/ Create or obtain the root CA X509 certificate. 2/ Obtain all intermediate signing authorities. 3/ generate a leaf X509 certificate and have it signed by the authority immediately higher in the trust chain (either an intermediate CA or the root CA if you're using ...


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SSL Labs uses the Mozilla trust store What is this "trust store" mentioned? Is it in my browser? On the server I'm testing? On the ssllabs server? The trust store is on the SSL Labs server. They use the Mozilla trust store. Details below. Why are there two paths? Where do they come from, where are they configured? Because both the ...


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site is only available in HTTPS HSTS in this case at least notifies that browser that the site will not be available in HTTP for the foreseeable future. Once the browser knows this (i.e. after the first visit) a downgrade attack like sslstrip will fail, because the browser will not connect with insecure HTTP to the site. The secure flag for cookies ...


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Why are there two paths? Were do they come from, where are they configured? A signature is created by using the public key of the issuers certificate. Two certificates can contain the same public key (typical after re-issuing a certificate) and this leads to alternative trust path if both of these CA certificates are included in the trust store. ...


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1 - The "trust store" depends of you browser / operating system. For Firefox, it's inside firefox, for Chrome on windows, it's the trust store of your windows There is two path because ssllabs know two certificate that can be root. If your visitor have any of the two in their trust store, your certificate will be valid. 2 - Chrome may complain because if a ...


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Such compromises already happened and DigiNotar is just on example. In effect the attacker could impersonate almost all certificates this way, because for most certificates it does not matter who signed it but only that it was signed by a CA trusted by the browser. There are few exceptions which are thus safer: Chrome and Firefox (and IE with EMET?) have ...


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The compromise of a Root CA does not mean that all certificates signed by that trusted root are indeed compromised. Rather, it means that fraudulent certificates can be made for man-in-the-middle attacks and signed so they appear trusted in a browser. When you submit your Certificate Signing Request (CSR) to a Certification Authority (CA), they are ...


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Well the issue here is that Microsoft should have updated their Root Certificate Program member list PDF document and notified their corporate and government customers at the very least, which they haven't. Also, SilverlightFox is wrong: you cannot "simply check your Windows OS's certificate store for root certs.", as this only provides a list of currently ...


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I found the answer from (RFC2818) http://tools.ietf.org/html/rfc2818#section-3.1 According to rfc If a subjectAltName extension of type dNSName is present, that MUST be used as the identity. Otherwise, the (most specific) Common Name field in the Subject field of the certificate MUST be used. Although the use of the Common Name is existing practice, it is ...


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How exactly is this protecting against a malicious DNS routing? Not at all. If an evil guy has a valid certificate (e.g. from a hacking a CA) and then manages to man-in-the-middle you, then your connection is hacked. I was expecting a challenge response using the public key of the server, but I cannot find it. In order to do this you would have ...


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No, new root certificates are added on a regular basis. Microsoft have a Trusted Root Certificate programme enabling CAs to enroll. This happens with most products that handle certificate verification. For example, this is Mozilla's list where you can see that there are several added per year. For Microsoft's list you can simply check your Windows OS's ...


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The OCSP connection, like standard HTTP connections, made by Firefox may be affected by addons, notably ad blockers. To verify the issue, take the normal path of disabling the addons, and then once the addon is identified, leave it enabled and disable the ad blocking subscriptions, to narrow the cause. However, each test must be run after a clean restart of ...


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That should never happen. User is requesting your site via https://example.com. The user's browser will expect the server to provide a cert with hostname of example.com. Hacker can not MITM that as hacker will not have the example.com private key to sign a message and authenticate as example.com. User's browser will report an severe warning. If hacker ...


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To set up general TLS decryption Security Onion will need to have a certificate trusted by your endpoints. Usually this certificate has a CN of * so it can sign anything. So you'd generate a TLS keypair for encryption. Its cerificate will need to be added to your root store either on your ActiveDirectory Domain Controllers, some other central store for ...


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You are combining a few components. TLS/SSL is rather complex because there are so many individual pieces which fit together. The public key is part of the cert and the key exchange and server authentication are two independent steps which (can) use different algorithms. The server first needs to be authenticated because DH and variants are vulnerable ...


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Yes the hostname on the cert must match the hostname portion of the url the cert is requested from. That is a requirement because there is an expectation that SSL not only secure the communication (encryption) but also ensure the user is connecting to the proper server (authentication). Without that requirement it would be trivial to spoof users with a ...


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Mike Scott posted a great answer. But it might be worth noting why it matters. On a technical level your data will still be encrypted. However your users might be turned away because they can't trust the certificate as most browsers will warn them of the error and usually make them perform extra steps through warning messages. The messages are made to look ...


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It's not clear to me if Java is part of your question or not. The Java Crypto API can load a keystore from any input stream (and store a new/modified one to any output stream), but many applications and libraries (and the keytool utility) only support files. See e.g. ...


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First, it's not a URL, it's a host name or domain name. The host name is one part of the URL. http://security.stackexchange.com/questions/92838/is-it-neccessary-the-website-certificate-must-have-site-url is a URL, and the host name is security.stackexchange.com. Next, yes, at least one host name in the certificate must match the exact host name used to ...


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I do not know Chinese but by looking at qq.com I see that the login page is on HTTPS. This is just an example that the HTTPS pages may not be the front ones. You will find the same case in some "portal type" European sites (wp.pl being one example): the front page (with information) is on HTTP and any sensitive one (email for instance) is on HTTPS. To ...


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The privacy of browsing information depends on vulnerability of SSL that your service provider use. If a website using a vulnerable protocol (like as SSLV3 that vulnerable to POODLE attack) or weak signature algorithm (like as Diffie-Hellman (DH) key exchange), absolutely your information is in danger. but for example if a website using TLSV1.2 with ...


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Let's look at how such a thing might play out: A classic example is the Dual-EC DRBG which employees a back-doored RNG to create a general attack against TLS. The other half of this attack beyond the vulnerable RNG is a mechanism for revealing to the attacker the state of the RNG at the time of use to allow the attacker to predict the remaining "random" ...


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There are some classes of PRNG weaknesses which require the attacker to obtain multiple numbers in order to predict the next number in the sequence. Using two PRNGs would compartmentalise the risk, in the event the "public" chain can be predicted, the "secret" numbers may still be unpredictable. Honestly I wouldn't consider it that significant but it could ...


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Encrypted key files do have some value, but generally the value is limited because the practicality of serving a 24/7 operation dictates that the key must be stored on the filesystem somewhere in unencrypted form. The alternative of the password being typed in by an administrator each time a server is restarted is terribly impractical and creates risk of ...


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I can't tell you how NVD came up with their, let's call it baseline rating. But I can tell you that not all vendors have followed that baseline rating. Ratings survey (AV:N/AC:M/Au:N/C:N/I:P/A:N), 4.3, NVD And if manually change this to (AV:N/AC:M/Au:N/C:P/I:P/A:N), then you get Overall CVSS Score 5.8. (AV:N/AC:M/Au:N/C:N/I:P/A:N), 4.3, Juniper. Same ...


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Key Usage error The key usage field shows exclamation mark because this field is marked as critical. This is not an error. why is it showing "Thumbprint alogrithm as "sha1" Beacuse the certificate thumbprint (the field below it) is created using SHA1.


1

You are absolutely correct, when there is no valid HTTP inside of the SSL encryption, a decrypted flow will not work through a SSL intercept proxy. One of the things you need to do before implementing SSL intercept is that you need to identify SSL based applications that are not http-based to prevent denied access (handling through Whitelist). I can only ...


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Digitally-signed struct for RSA signing And what's this digitally-signed structure? It's defined in TLS 1.1's Section 4.7. Cryptographic Attributes: In RSA signing, a 36-byte structure of two hashes (one SHA and one MD5) is signed (encrypted with the private key). It is encoded with PKCS #1 block type 1, as described in [PKCS1A]. MD5 hash in ...


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How can I add certificate pinning for other domains to my web browser (e.g. FireFox)? I don't think it's got a GUI in Firefox. For Chrome see Tom's answer. Is there a reason why there is no option to "Pin this certificate to this URI" when viewing the details of a certificate in a web browser? Yes. It's support hell when it's time for a key ...


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What you describe is https with self-signed certificates, i.e. Setup a new server with SSH, it makes it's own keys. Setup a https server with a self-signed certificate. ssh to a new server and get a new fingerprint: "This is new, accept?" Connect to the new server with the browser. You get a warning but can tell he browser to add an ...


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You can do it in Google Chrome with chrome://net-internals/#hsts : In that screen you can consult the pinning state of a website (HSTS, HPKP and preloaded) but you can add certificate pinning for any domains too : In the Add domain section, you can specify for any domain : If you want to force HSTS If you want to pin some certificate : you need to ...


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Yes, your ISP has records of your attempt to visit the original page. That request left your browser, went through the ISP and to Facebook, which sent back a response of a 503 error, which your ISP also has records of.


0

Yes Pi is appended to the body; (re)read the paragraph labelled Blockwise Privilege at the top of the page. Remember HTTP and thus HTTPS is a stream protocol; if you make a request to upload say 100 gigabytes uncompressed video you probably won't do it in a single step. To restate a little more finely: Step 1 Mallory's code causes something in Alice's ...


0

The decodings as HelloRequest are indeed as @Stackz suggests because Wireshark can't decode encrypted records. It tries anyway, and only if it detects a decode failure it suppresses the decode and displays "Encrypted Handshake Message". Here it didn't detect the decode was completely bogus. Every handshake message (within a handshake record) begins with a ...



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