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0

Well, in theory, there's no need for HTTPS for browsing that type of material...however, I'm pretty sure Google made HTTPS active for all browsing, even non-sensitive stuff. To clarify, if you just go to www.google.com it is indeed HTTPS.


2

Is there a way for a TLS client to inform the server that it doesn't intend to resume its authenticated session(s) anymore? Yes, by sending an Alert with a Fatal severity. From RFC 5077: 5.1. Invalidating Sessions The TLS specification requires that TLS sessions be invalidated when errors occur. This is an apparent reference* to the ...


0

Can anybody suggest a best-practice for a start-up business situation? For both cases where you need such solution for your startup or you need to design a solution yourself, you could take a look at two email services that are featuring end-to-end encryption that I've signed up to are Protonmail (https://protonmail.ch/pages/security-details.html) , ...


3

Will browsers recognize HPKP header on subdomain if I set it only on domain.tld and add includeSubdomains in it? If the user never visits domain.tld and the HPKP header is only send on requests to this domain then the browser will never see the HPKP header. But only after the browser has seen the header it has any effect. Once the browser has seen the ...


4

@atdre points to a tool that should allow detecting whether a given server supports TLS 1.2, but this is only part of the story. In SSL/TLS, the initial steps of a connection are the handshake in which a number of parameters are agreed upon between client and server, including the protocol version that will be used. The client announces the highest protocol ...


3

Active assessment of all known IP addresses and hostnames is the best method to audit an infrastructure to full compliance. sslyze --sslv2 --sslv3 --tlsv1 --tlsv1_1 --targets_in=target-list.txt --xml_out=sslyze.xml You can get sslyze here -- https://github.com/nabla-c0d3/sslyze You may also need a developer who understands XML parsing in order to best ...


3

You may also want to look at this question, which also touches on the subject. I understand that an SSL / TLS certificate, verified by a public CA, will enable transport security on SMTP between servers. However, I don't see how this could help with transport security between the server and a client. At best, it seems like the client's outgoing ...


5

In short, they're both crypto key generation tools, but keytool has the additional feature of manipulating Java's preferred key storage file format, the KeyStore. Java strongly prefers to work with keys and certificates that are stored in a KeyStore (also called a TrustStore when it's only got certificates in it). It is possible, but not trivial, to get ...


1

Both OpenSSL and keytool have the same purpose: generating/storing keys and certificate(s) (chaines). The thing is that Java can only work with certificates/keys contained within its keystore (JKS). Those certificates and keys are generated using the keytool library, not by using openssl. As you rightly pointed out, keytool will always need a keystore in ...


0

(The Most Common Java Keytool Keystore Commands) Java Keytool stores the keys and certificates in what is called a keystore. By default the Java keystore is implemented as a file. It protects private keys with a password. Whereas OpenSSL generates first RSA Private Key (1024 bit RSA key which is encrypted using 3DES and stored in a PEM format so ...


0

SSL termination or SSL proxy products like Bluecoat need to be on your network and considering the cost, the installation procedures involved and the normal security policy any organization would have who installs these products - the threats of a malicious attacker using a commercial SSL termination product is almost zero. OTOH - a trusted insider with ...


1

The Pre-Master Secret is derived from the above random numbers (except where Diffie-Hellman is used). It is then encrypted with the Server's Public Key and sent to the Server. the catch is, this encrypted message can ONLY be decrypted by the Server's private key. so if an attacker knows/has the server's private key(the golden key), then its all over already ...


1

Section 6.4.3 in the RFC heavily implies that *.*.example.com should validate, I read this section differently. In my opinion it clearly says that matches SHOULD only be done against the left-most label (6.4.3.1) and that if a wildcard is the only character in the label like in your case then it SHOULD only be matched against the left-most part of the ...


5

What browsers do is subject to change at the whims of whoever maintains them, and they do so without any proper documentation. The treatment of wildcards in dNSName entries in certificates is formally defined in RFC 2818, which would imply that, e.g., *.*.example.com would match a subdomain name that's two levels down example.com; it also says that f*.com ...


10

SSL/TLS are protocols. OpenSSL is an implementation of these protocols. It has two libraries: libcrypto which implements a set of encryption algorithms, and libssl which implements TLS protocols and its previous SSL. If there is an error in the implementation of a given protocol, it does not mean the problem is the protocol itself. HeartBleed is just a ...


21

If you look at the Heartbleed summary: The Heartbleed Bug is a serious vulnerability in the popular OpenSSL cryptographic software library. This weakness allows stealing the information protected, under normal conditions, by the SSL/TLS encryption used to secure the Internet. SSL/TLS provides communication security and privacy over the Internet ...


0

When a user access a website, in order to encrypt communication between the the user and the website, a symmetric key is to be use. Yes. *In order for the symmetric key to be used by both the client and server, information about the creation of the symmetric key must be encrypted using the asymmetric key Yes, unless it is diffie-hellman. ...


2

A certificate is your public key and some information about the site and then a lifetime. All this is signed by the issuer CA. The certificate is public and thus also the public key, but the private key is not published. One of our SSL certificates has expired and along with that so has the keys. While the certificate will expire the public and ...


2

With modern Intel CPU's (and we're talking 5-7 years now...) there is no significant performance hit on the computation involved in an SSL connection. So - from a performance perspective there is no reason not to use SSL everywhere. Another caveat is the vulnerability of mixed content on your page. You should not be referencing HTTP resources on an ...


1

First, I think that you're confusing some terms. The term is "digital certificate", "certificate", or simply "cert". Not "digital certification". If you really mean "digital certification" then this answer is likely wrong. Yes. Symmetric keys are used for bulk encryption because symmetric encryption algorithms are much faster than asymmetric ones. No. This ...


5

As with all things in security, using HTTPS is a trade-off. You're trading some performance and potentially customer inconvenienace for improved security and other possible benefits (for example google boosting the ratings of SSL enabled sites). Only you can answer whether that's worth it, as only you know what your site does and whether the trade-off is ...


4

If I am not mistaken, importing your own SSL certificates is just for the connections which you make to the device's own web interface so that won't help you to accomplish your goal. What you would need to do is: Create your own root CA Make those devices trust your own root certificate Redirect all SSL traffic from those devices to your proxy When a ...


0

You can use your computer as a proxy server using "Squid" and configure SSL dump by decrypting the traffic, analyze it and re-encrypting it again and send it to its destinations. You will have to import the certificate created by Squid to your connected devices.


3

You can have a backup certificate from a different CA but you cannot serve multiple leaf certificates (i.e. certificates matching the hostname) within the same TLS connection. You can also not have multiple signatures (i.e. by different CA's) on the same certificate which is a similar question often asked in this context. But you could use different ...


2

TLS only allows a single cert. You'd need to have some monitoring in place to check for this issue and automatically reconfigure your web server upon occurrence. You can get the same CSR signed by multiple CAs. Each time you will get a separate cert signed by that single CA. You are likely better off with completely independent keypairs and CSRs for each ...


2

These answers are great. But I often have to give a simplified answer without all the jargon. HTTP - It is not encrypted and the data sent over the line could be easily read. HTTPS - It is encrypted and verified by a trusted party the data is being handled by the correct source. HTTPS (Self Signed) - It is encrypted but there is no verification by a ...


4

Tor provides you anonimity. HTTPS protects (encrypts) the content of your data. HTTP does not provide none of these. Tor provides anonymity but does not protect the exploitation of an insecure application to reveal the IP address of, or trace, a TCP stream. Running HTTP over Tor means your communication data could be read and thus compromising your ...


7

Tor provides anonymity which HTTPS does not provide. HTTPS only provides end-to-end encryption, but a man in the middle can still see where you are connecting to and might find out more (i.e. which sites your are looking at in detail) by doing statistical analysis of the sniffed traffic. Tor tries its best to hide the meta-information like source and ...


18

Security difference First, let's talk about SSL (now called TLS by the way), which adds the 'S' at the end of HTTPS and is in charge of "securing the communication". The clue to answer this question is indeed to fully understand what we mean by "securing the communication". SSL, no matter if it is a self-signed certificate which is being used or one signed ...


4

Without warnings for things like self-signed or expired certs, inappropriate cipher suite selections, and other bad HTTPS configurations, the presentation of a website's state of security to the user becomes binary - either you have HTTPS on the site, or you don't. This would hide a number of nuances which can significantly affect exactly how much the "S" in ...


32

The purpose of the warning is that by using HTTPS, there is an expectation of proper security, but a self-signed or expired certificate has vulnerabilities that the user needs to be aware of. The "risk" is that one thinks they are properly secured, but they are not fully secured, as opposed to HTTP, where one knows there is no encryption at all. There ...


5

The other answers are right that in practice Cloudflare can't provide their full services as effectively without introducing this kind of security risk. Roughly speaking, Cloudflare does two things: They mirror your site, and can serve it from their own servers (their CDN). This way, if your site is getting hit with a DDoS, they can absorb the traffic ...


5

Potentially Cloudflare could work in a pass-thru SSL mode. However, it would not be as good at protecting against DDoS attacks. In pass-thru mode, clients would make a TCP connection on port 443 to Cloudflare, which is forwarded to your web server. The SSL setup takes place between the client and your web server, so while the connection goes through ...


2

What's the content of your website? Is it anything anyone anywhere in the world could want to access without other people knowing about it (governments, marketers, snoops on the same wifi network)? Remember that what might be perfectly acceptable to view in your culture might not be acceptable elsewhere (like opinions about politics, sexuality or religion). ...


8

It can't work any other way because the way cloudflare works is that they mirror your files for your users on their own servers. To request the files, clients connect to Cloudflare instead of your server. That means their browsers expect that the connection is encrypted with a valid TLS certificate from cdn.cloudflare.com, not from your website. End-to-end ...


23

From what I understand, no, Cloudflare couldn't work any other way. Cloudflare analyses the connection before passing it to your webserver to ensure that it's correct and coming from a legitimate client. In order to do this, it needs to be able to see the contents of each packet from and to your server. With SSL/TLS, each packet is encrypted and therefore ...


4

Is HTTPS needed in this case? In every case that I can think of HTTPS is beneficial. The trivial case is if you don't have sessions, why would you need a secure connection if there are no sessions and everything is public? Having a secure connection actually helps your Google PageRank, and it also helps the user feel more secure by visiting your site ...


2

I do not think there is a significant security advantage for using it in an HTTP header (not counting the URL which is sent in the request line that starts the HTTP request, where you have to be more cognizant of it being logged in your browser history or server logs) vs being in a POST request body. The advantage of sending keys in an "Authorization header ...


2

If the transport itself is secured (i.e. https) an attacker can not sniff the data. But it might be logged at the server side and the server might later be compromised or some security leak might cause the log files to be publicly visible. Such log files usually contain the URL and they might contain other lines from the headers like User-Agent, Referer and ...


0

I would use HTTPS with certificates signed by a CA you create, if you don't want the cost/hassle of using a trusted CA. Then merely verify your keys against your own CA. For example see this guide for how to create your own CA, and sign your own certificates with this CA, though for your purpose, you do not need to install your root certificate into ...


2

I will try to address this at network/protocol level an leave the method you send them (IE email's) up to you. If you have thought on the transfer medium that we can address that as well. Base on your post, I am guessing these are internal use only and no external access is required. If this is not the case, buy a third part cert. Internal only, your ...


1

Some people do not trust the curves that are used for ECDHE, believing them to have been compromised by the NSA or some other agency -- see for example this comment by Bruce Schneier stating that he now prefers classic discrete log crypto instead of ECC. If you don't trust ECDHE then DHE is the only algorithm that provides perfect forward secrecy, and so ...


3

Some servers may use curves likes Curve25519, Curve448 or P-521. Clients not supporting it will need alternative key exchange methods. Some people don't trust NSA-blessed NIST curves like P-256 and P-384 (check out SafeCurves to see why) and might want to block ECDHE until safer curves get adopted. Some people don't trust ECC at all and DHE is (SFAIK) the ...


2

You can use the Internet Protocol Security (IPSec). This way your LAN communications are both authenticated and encrypted for each IP packet of a communication session. It is not a problem whether your machines are running Windows or Linux based operating systems. Note that you can also use it in conjunction with Layer 2 Tunneling Protocol (L2TP) that ...


0

According to tech support for Niagara AX, "HTTPS Tunneling is not supported". This contradicts what I have heard from other sources, so while I will put this as the "official" answer to my question, I may update it if other information becomes available. In other words, the point of my question, namely to find out whether certain settings or file formats ...


2

Yes, using MD5 is safe. When a client wants to authenticate, the server sends a random salt value. The client uses that value, along with the password to generate a MD5 hash. Because a random salt is used, an attacker can not use a dictionary attack. Also, because the salt is changed each time a client authenticates, this is no ability to replay old ...


2

Using the source listed for the SSL Socket object in the Android API Client Side +-------------------------------------------------------------------+ | Protocol | Supported API Levels | Enabled by Default (API Levels) | +-------------------------------------------------------------------+ | SSLv3 | 1+ (BASE) | 1+ (BASE) ...


1

Yes, your guessing is correct. OpenVPN has a built-in certificate management feature. This is the role of the Easy-RSA, I am guessing you already know that. The Easy-RSA is an RSA key management package based on OpenSSL. It allows you to build your own root CA and generate and manage the client's certificate/key pairs and the server certificate/key pair. ...


0

In TLSv1.2, and only in TLSv1.2 - if the client hello include an extension called "signature_algortithm", the server may sign the certificate with any of the methods mentioned in the extension, regardless the cipher-suite it choose to work with.


0

What I can see, is that the main difference is not about "SHA1" but about the certificate chain. See the icons. Both "SHA1" messages are locked with a green icon, but the part about about the identity of the website is different. GOOD: *.mail.live.com . Certification owned by Microsoft, verified by Symantec Class 3. According to digicert.com, no error or ...



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