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41

No, SSL uses a symmetric key so an attacker is unable to decrypt the message he has just captured. However, SSL is vulnerable to a traffic analysis attack. E.g. If you have 2 messages of very different lengths like "Execute order 66" "This is a very very very very very very very very very very very very very very very very very very very very long ...


28

The hostname is included in the initial SSL handshake to support servers which have multiple host names (with different certificates) on the same IP address (SNI: Server Name Indication). This is similar to the Host-header in plain HTTP requests. The name is included in the first message from the client (ClientHello), that is before any identification and ...


16

There are IT security companies which provide services like code auditing (most often along with other services like penetration testing, etc.). You contact them, describing your needs, then if this fall under their competences they will send you an estimate.


12

No. See How does SSL/TLS work?: basically, every time you transfer data, it's encrypted with a symmetric key generated for that particular transaction. The public key is only used to verify the server's identity, so even if the attacker knows it, they can't tell what message you sent simply by looking at the ciphertext.


11

SNI is there for virtual hosting (several servers, with distinct names, on the same IP address). When a SSL client connects to a SSL server, it wants to know whether it is talking to the right server. To do that, it looks for the name of the intended server in the certificate. Every evil hacker can buy a certificate for his own server (called ...


10

You are making two assumptions here, that would need justification: NSA / "other agencies" invest in supercomputers. They do ? How exactly would you know that ? Did you read it on the Source of All Truths, i.e. "the Internet" ? NSA's unique goal in life is to break TLS sessions. Considering that the NSA has been created in 1952, while SSL was first ...


8

No actual break involving SHA-1 and using a structural weakness of SHA-1 has been currently fully demonstrated in academic conditions, let alone in the wild. The best we have right now is a theoretical collision attack that should allow an attacker to compute a SHA-1 collision with effort "about 261", which is huge but still substantially less than the 280 ...


6

Well in the case of SSL, it would not be possible because of the way SSL works. The message would not be encrypted with the public key. Instead, the public key would be used to share information between the two persons in order to agree on a symmetric session key. This key will then be used to encrypt the "order", so you can't replicate this on your own ...


6

The fact that you are communicating to some server obviously cannot be hidden from IP. The packets have to leave your machine, enter the network, be routed to the destination, and be delivered. It's not a secret that you're contacting a server that delivers pages from https://www.fred.com. However, the URL does not contain the IP. Instead, it contains ...


6

You just need to add the tool certificate in the trust store of the client, so that the client trust your "tool as a server". Then in order not to have any errors, every time the client tries to open a TLS connection, you have to clone the actual cert with your custom CA: Client tries to initiate connection with the server, it goes through your proxy The ...


5

The power in a certificate is NOT in the certificate. It is in the private key. When a server "uses a certificate", it really uses the private key; and the server shows the certificate (that contains only the public key) to the client. The certificate is a proof that a given public key belongs to a specifically named entity. For instance, the certificate ...


5

There are many likely reasons. 99% of popular web sites support TLS 1.0, but only 58% support TLS 1.2 (SSL Pulse, 4/5/15) The existence of strong encryption does not imply the use of strong encryption The use of strong encryption does not imply the correct use of strong encryption The NSA is arguably interested in many, many things aside from TLS web ...


4

As the other answered, it is generally not possible. However, there is always the possibility of having some information leaking depending on how the message is structured: an observer could read the encrypted message flow between party and obtain some of the meaning of these messages based on size or flow.


4

To answer a different part of your question: No, even if the message was encrypted using the public key, real asymmetric encryption systems will not let the attacker easily try their list of possibilities and look for a match with the ciphertext. This exact concern is why asymmetric encryption is always done using a probabilistic encryption scheme, in which ...


3

This is a typical setup in companies and is called SSL interception, SSL visibility or something like this. The main idea is that there is nothing which prevents attacks using TLS connections, because TLS only secures the transport and neither the server nor you can make any assumptions about the security of the server or the risk associated with the ...


3

Did you take a look at this answer? There are a few tools listed. However the key point for you is to have a certificate that your client will accept. To answer your question, in its simplest form you need: A valid SSL certificate (signed by the CAs that are trusted by the client) Control of DNS resolution (but if you control the environment you'd have ...


3

Just let them buy a new one. You may be thinking of a process like in DNS ownership transfer. But there is no such thing for certificates. Anyone who can answer an email for admin@example.com will get a certificate for example.com. It's as simple as that.


3

Define a specification If you are writing/developing a new protocol before you cut code, you should start by writing a specification like a Request For Comments (RFC). Even if you never intend to publish your protocol the process is the important part. The RFC would be the basis of any assessment that you want to have done in the future. In addition to ...


3

So how can I ensure that when I send a user to my server, and they are confronted with the "self-signed certificate" warning, they are able to decide for themselves whether to trust it or not, instead of having to believe the skewed picture that their software paints for them? If you are not using pre-defined trust anchors (e.g. the root CA of the ...


2

Depending on language and environment: US DHS and a third party host SWAMP (software assurance marketplace). You must apply for access and membership, but it's worth looking into. SWAMP


2

Super computers have a lot more use than just 'breaking' Cryptography. the NSA could be using super computers for anything from Big Data Analysis to Breaking a specific Encryption.


2

It depends on the exact vulnerabilities which have been found, but unless there are very specific threats like buffer overflow, code injection, etc. which have been found, the general answer is that if you do not use SSL, then you are not concerned by SSL weaknesses. SSL goal is to provide communication channel security through confidentiality, integrity ...


1

Considering its trivial to get a free signed SSL cert, I wouldn't even mess with self-signed certs. It builds bad habits in users and is just asking for trouble. http://www.startssl.com/


1

When you have secure(!) contact with all of your users over a different medium, you can send them the root certificate of your own certificate authority which you used to sign the certificate of your website and give them instructions how to add it to the list of trusted certificates of their web browser (or maybe even a handy install script which does it ...


1

Edit: The question author made significant edits to their question after this answer was posted. This answer is based on an earlier version of the question which gave the impression that they were asking about a usual public website. You can not explain that a self-signed certificate is fine, because on a public website it is not! The other question you ...


1

the only defense against this is using Key Pinning the problem is that that only works as soon as the client has connected with the web service at least once (to have the proper value for the pin) and another problem can be that the pin holds for a long time so replacing your certificate or key is not possible while the pin holds (unless you plan ahead and ...


1

As a rule, each should be unique. The private key associated with a certificate needs to be secret. If that secret gets out, then they don't offer any protection. You can assume that anyone who has possession of a device can extract the key from that device, so you want each key to be unique. Certificates needn't be signed to offer protection. It helps, ...


1

A certificate is used to make sure that you connect to the correct device, that is that no man-in-the-middle is intercepting the connection. If you employ the same certificate on lots of devices which are shipped to lots of different customers the goal of proper verification if your own device can not be reached. Apart from that each of these devices would ...



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