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You are missing a very important part of a Digital Certificate here. That part is Digital Signature. Basically, a Digital Certificate consists of 3 parts: A public key. Certificate information. ("Identity" information about user, such as name, user ID, and so on.) One or more digital signatures. A digital signature an encrypted hash of the ...


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SSL certificates have an extension field that defines what a certificate is allowed to be used for. When you buy a certificate from VeriSign with your certificate signing request, it typically will not include the extension permission for signing downstream certificates with your certificate; especially for any domain you don't have authority for. Take ...


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The site at http://cipherli.st has config snippets for setting up Qualys-rated A-Grade TLS for Apache, nginx and lighttpd. It also includes statements for HSTS, OCSP-Stapling and X-Frame-Options.


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SSLProtocol -all +TLSv1.2 +TLSv1.1 +TLSv1 -SSLv3 -SSLv2 SSLHonorCipherOrder on SSLCipherSuite "EECDH+ECDSA+AESGCM EECDH+aRSA+AESGCM EECDH+ECDSA+SHA384 EECDH+ECDSA+SHA256 EECDH+aRSA+SHA384 EECDH+aRSA+SHA256 EECDH+aRSA+RC4 EECDH EDH+aRSA RC4 !aNULL !eNULL !LOW !3DES !MD5 !EXP !PSK !SRP !DSS"


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If you don't want to give away your site's name to these other websites, you can also test it with... openssl s_client -ssl3 -host <your host name> -port 443 If it doesn't connect then you're ok. But also make sure that your openssl is working properly with your site... openssl s_client -host <your host name> -port 443 Disabling sslv3 also ...


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The Same-Origin Policy does not differentiate between HTML and JavaScript in the context of data-access. An HTML form exists within the DOM within the website's context, and JavaScript is bound to this same context. In both implementations Cross-site Scripting can be used to undermine the Same-Origin Policy and obtain sensitive information.


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Client software that is susceptible to downgrade attacks is defective, in the sense that it purposely does things outside of the standard in order to support server software that is defective. Normally, the client announces (in the ClientHello) its highest supported protocol version number (e.g. "3.2" to mean "TLS 1.1") and then the server responds (in the ...


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Short version: interoperability sucks. Long version: Currently there are four SSL/TLS variants in common use: SSLv3 (1996) TLSv1.0 (1999) TLSv1.1 (2006) TLSv1.2 (2008) Each protocol supports a variety of ciphers. Older protocols have wider, more uniform cipher support. Newer protocols may implement smaller subsets of the ciphers available, and ...


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There are secure non-POODLE-vulnerable ciphers which you can use with SSLv3 - POODLE only impacts variants with CBC. The RC4 ciphers, for example, are not vulnerable to POODLE. Now, RC4 is a tricky thing. It's considered breakable (but not really actively broken), but since it's the best workaround for things like BEAST and POODLE, it's heavily used and ...


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The Poodle attack model is one where the attacker triggers the requests (normally with some Javascript in the client -- note that, in that case, requests will be GET, not POST, since that "evil Javascript" will be served as part of an unprotected Web page load from another site, and the same-origin policy will prevent arbitrary POST) and manipulates the ...


1

In the scenario you have outlined it is in fact possible, at least in theory, to sniff the connection. Okay, so WEP is easy to crack, and if you are using, you should stop and get on to WPA2, which is far more secure, and nearly impossible to break. In each of these cases you will need to have some sort of password/key set up. If it's just your own access ...


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I see where you are going with this, and it's good, out of the box thinking. Unfortunately it isn't likely to work in many cases - if a browser supports SSLv3 chances are it supports bad ciphers too. My advice would be to put this system behind a web proxy where you can control the ciphers and protocols, and let the client connections terminate there. The ...


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Answer: Let's think about it. For governments that can afford it, point-to-point encryption of voice calls is not hard to do, even with cell phones. So for the voice calls that aren't encrypted and are easy pickings, maybe that's what they want heard? (Counter-intelligence is not entirely unheard of now is it?) On an individual scale, it is possible to ...


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In your case I would recomend a VPN server. This appears to be a very secure site, and you hardened the server side very well. Using a VPN infrastructure will put another barrier between the server and the attacks. If you already have the users receiving and entering the authorization code, they will be able to connect to a VPN without much trouble. In my ...


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If your server does not support SSLv3, then it does not support SSLv3. "Protocol downgrade attacks" are methods to force a client and server to use a protocol version that they both support even though they both know at least one newer version that they would have wished to use, given the choice. Anecdote: I am French. Back in 2005, I was walking in the ...


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Firefox browser provides the easiest way to do such testing via the advanced settings in about:config where security.tls.version can be of the following values 0 - SSLv3 (set max and min value to this) 1 - TLSv1.0 2 - TLSv1.1 3 - TLSv1.2 What you will see when the website does not support SSLv3 is this: Please remember to set it back to max 3 and ...


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It doesn't necessarily matter what your server uses by default - most servers and clients are configured to negotiate the highest protocol available. A major aspect of the POODLE attack is that an attacker can cause connection failures in a higher (non-vulnerable) protocol, and downgrade the victim to SSL3. Then they can exploit the vulnerability in SSL 3. ...


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As per Certificate authority Guideline, Wildcard SSL certificate is only supported for security of single level sub-domains with the same host name. Without any limit Wildcard SSL can secure unlimited single level sub-domains.


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There is no new version of sslstrip since 2011 and the feature is already there. How It works: First you need to know about the HSTS headers. SSLStrip will work when server sends HSTS header for the first time and you intercept the traffic in between don't allow the header to reach to the client. The important header field of HSTS that allows client to ...


0

The "grade" that you get from such tests is mostly meaningless. What kind of sense does it make to say that your server is "sort of" secure, but not completely ? Does it mean that attackers will still break in but won't be so smug about it ? The important point about SSL security, of security in general, is that it often is all-or-nothing: the attacker ...


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A session id should be a Cookie parameter, and should never appear in the URL. Any value in the URL A will show up in the referer header, as well as access log files. A web application will end up transmitting authentication credentials to other websites, and storing them in plaintext on the filesystem. Additionally, when you pass a session id in the ...


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There are two distinct things here. One is about the number of hostnames that you can put in a certificate. The other is the notion of "wildcard names". In the Subject Alt Names extension, you can put "alternate names" of type dNSName. Each of them is an "acceptable server name" (i.e. clients will accept the certificate for a server that purportedly uses ...


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A wildcard certificate matches a pattern, not a hostname or set of hostnames. It's issues to *.example.com, meaning any host of format [subdomain].example.com will match. It is notable perhaps, that it is limited to a single level so the *.example.com wildcard cert could be used for sub1.example.com and sub2.example.com, but not deeper.sub1.example.com. ...


0

I guess you want to enroll users by POSTing CSRs. There is already enrollment schemes builtin browsers so you dont have to POST CSR's. Those enrollment schemes will also automatically install the client certificate in the browser store, so Everything is done in one shot. Here you have Everything to get started: ...


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Some portions of your question need to be clarified. The SSL/TLS encryption is based upon the cipher suites supported by both the client and the server. Not the certificates issued to each social networking site. The certificates issued do not have a bearing on a website's vulnerability to POODLE. The fallback to another SSL version is only performed if ...


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TL-DR yes parameters (not keys) can be shared. First, don't say "parameter keys". Parameters and keys are related but different. The whole point of parameters is that they define a mathematical group within which keys are chosen and used. Generating parameters is costly (moderately so for DH and DSA, much more so for ECC); generating a key for given ...


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I wrote an article on how to get an A+ on the Qualys SSL Test and it contains details of favourable SSL configs: ssl_ciphers ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!MD5:!DSS; That's an NginX config so you may need to change the format slightly as it looks like you're using ...


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I presume from your ssl.conf setting that you are using the mod_ssl module from Apache web server. This module relies on OpenSSL to provide the cryptography engine. From the documentation on OpenSSL, it states: Protocol version: SSLv2, SSLv3, TLSv1.2. The TLSv1.0 ciphers are flagged with SSLv3. No new ciphers were added by TLSv1.1 You can confirm ...


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POODLE is a protocol problem, not a cipher problem. (In fact, it works with both AES and DES, so you can see it's independent of the cipher used.) Disabling SSLv3 ciphers is not necessary (and, as you've discovered, probably not desirable). Disabling just the protocol is sufficient to protect against POODLE.


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I've published a blog on how to disable SSLv3 in some of the most common bowsers and server platforms (https://scotthelme.co.uk/sslv3-goes-to-the-dogs-poodle-kills-off-protocol/). This should at least help answer the question on how to fully mitigate POODLE be you a client or a server. Below are the key details. How to protect your server The easiest and ...


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It forces clients who report that they support TLSv1.2 to use it, and causes all other client connections, those who only support a maxium of TLSv1.0 or TLSv1.1, to fail. At this point, unless you know exactly who your clients are and that they do, in fact, support TLSv1.2, (if this is in any enterprise Intranet environment, for instance) I would not ...


2

The server and the client are both important. SSLLabs.com has a client test, as well as a server test. There are more details in the How does SSL/TLS work? question, but quite simply, the in the SSL handshake, the client is the first to send the version of TLS it supports and ciphersuites it prefers, and then the server selects the highest version it ...


0

The websites themselves aren't at risk. The user's data while it's on the website's connection is at risk. This is especially true for people on public wifi where the likelihood of an attacker being in control of user's traffic is much higher. It's only in the case that an attacker exercises control over your connection that your data is at risk. ...


0

I whipped a one-liner for this yesterday. It tests for the availability of the SSLv3 protocol. There is probably a better way to search for a string that also shows that CBC ciphers are in use, but most people just seem to want to know if SSLv3 is available at all. A few things to note about this one-liner: Written for bash on Mac OS X so can't say for ...


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Its possible to make changes to the TCP/IP SSL levels, but not really considered a policy per say, You might be able to use a deployment service to make the changes using AutoIT (I make company wide changes with this as my deployment asset.


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If you implement SSL-proxying, you can configure your proxy server (e.g. Squid) to not use SSLv3 to any side of the connection (client-to-proxy and proxy-to-web).


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To disable SSL v3.0 support: In Clients: Mozilla Firefox Either Install the Mozilla add-on called "SSL Version Control" Or Type about:config into the navigation bar and press [Enter] Accept the warning and proceed Search for tls Change the value of security.tls.version.min from 0 to 1 (0 = SSL 3.0; 1 = TLS 1.0) Chrome Run Chrome with the ...


0

Basically, the key pair of the server works as a kind of passphrase for the HTTPS connection. The public key is added to the certificate, which is then signed by a certificate authority trusted by the client. HTTPS requires the website to get a certificate, as you mentioned. This certificate is must be trusted by the client, otherwise the client will deny ...


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To check if you have disabled the SSLv3 support, then run (replace "facebook.com" with "yourserver.tld".) openssl s_client -connect facebook.com:443 -ssl3 which should produce something like 3073927320:error:14094410:SSL routines:SSL3_READ_BYTES:sslv3 alert handshake failure:s3_pkt.c:1258:SSL alert number 40 3073927320:error:1409E0E5:SSL ...


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What is the Poodle vulnerability ? The "Poodle" vulnerability, released on October 14th, 2014, is an attack on the SSL 3.0 protocol. It is a protocol flaw, not an implementation issue; every implementation of SSL 3.0 suffers from it. Please note that we are talking about the old SSL 3.0, not TLS 1.0 or later. The TLS versions are not affected (neither is ...


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Not all apps in facebook support https. So if you play games in facebook or use other third party apps you will get a notification that these apps are only accessible via http. When you proceed your connection will degrade to http.


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The primary ramification is that the security of your private SSL/TLS key is ultimately out of your control. Technically, you could use a wildcard certificate, or a multiple domain certificate (Subject Alternative Name, or SAN, certificate). However; if you use a wildcard or SAN certificate, then the security of all of your servers is tied to the security ...


0

SSL is probably not the most "efficient" way, but I'm not aware of any alternative that would be worth going to. Mobile devices had WTLS to streamline the process for lower-bandwidth devices, but that's not a very viable system... While you could roll your own, the rule of thumb (for crypto) is never roll your own. Flaws have been found in SSL, and ...


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If you want your server to encrypt/sign outgoing traffic, then it needs its own private key. This is normal. What I think you are asking is about the security of having this certificate on a server that is ultimately out of your control. You will simply have to limit the exposure of this certificate and have processes in place to handle the event where you ...


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Android 4.1 (API 16), according to this: http://developer.android.com/reference/javax/net/ssl/SSLSocket.html


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In many cases, the intermediate certs do mean something. Sometimes it mean the Insurance level (how much the signer will pay you in the event of a fraudulent verification) or it can mean the validation level (only domain verified, or full verified with Company details and Everything). In this case, Comodo isnt even the top signer. Instead its a Company ...


0

I'm not asking how to remove the passphrase (I know how), I'm rather interested in how will my server be able to handle it and is it really a big security risk not to use a passphrase? I mean once the web server gets compromised, wouldn't it be easier to install a trojan horse? To give a slightly different perspective on this. Asking the ...


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One benefit could be that there are less customers per intermediate certs so if a cert is stolen, there are less people affected. Comodo has a very automated process in signing certs for customers so they may regulary create a new intermediate CA for their signing-server to prevent one cert to get too big to fail. But this is only a personal theory, to be ...


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I mean once the web server gets compromised, wouldn't it be easier to install a trojan hourse? Essentially correct. Once an attacker has sufficient control over your server, they can usually just swap out your encrypted certificate for a cheap or free SSL certificate of the type that only confirms that you have access to the server (which the hacker ...


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One way to do this is open the server up in your browser like so: https://[smtp server]:[port]. Then save the certificate that your browser encounters. For instance, https://smtp.gmail.com:465/ To do this quickly, I used Internet Explorer. To do this in a real browser you will need to override port "protection", as apparently internet users are toddlers to ...



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