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20

Modern cryptosystems are generally not susceptible to known-plaintext attacks. In terms of encryption algorithms, there are basically 3 algorithms commonly in use in TLS: AES RC4 DES (in 3DES) All 3 of these are believed to be resistant to known-plaintext attacks, and have been well studied for such attacks. The one thing I would wonder about are ...


11

That "charter" is rather down-to-earth; it does not specify that "TLS should provide confidentiality and integrity" because this is taken to be obvious; instead, the charter is a roadmap to the future TLS 1.3 and thus documents the desirable changes from TLS 1.2. As for the mailing-list messages you are pointing to, I think you are over-interpreting them. ...


5

In SSL/TLS the server is supposed to show its certificate as part of a chain. Theoretically, the server should make sure that the sent chain is correct, and the client is "morally entitled" to reject the connection if the exact chain sent by the server fails to validate. However, clients are allowed to make extra efforts; if they can validate the certificate ...


5

Maybe a silly question but are you certain you're not getting a ✓ meaning that the password you have entered has met the minimum requirements for the sites password policy? Such that the client side code is saying "yes, this is a valid password and I will accept it, although I have not yet validated the correctness." When you enter the password as ...


5

If nothing else, it's an API for checking passwords without any time delay. It has to be: if they had a time delay after every incorrect guess, it would defeat the point of live-checking the password. If you password is "password", then the server has to check seven incorrect passwords before reaching the correct one, and you can't afford to have a delay ...


5

They are designed specifically to not allow this. As you brought up yourself, that would be a massive security risk. If you want to be able to browse your own systems without clicking "confirm security exception" a million times, add the certificates to your trust store on your computer, using the "Certificates" MMC snap-in. This can be done even better ...


4

Because your browser comes with its own set of certificates. When you install a new version of Windows 7, it comes with Internet Explorer. Internet Explorer, like any other browser, comes with its own set of certificates that it trusts. All the web authentication is based on the fact that there are only valid certificates in your browser. How does ...


4

There is no global directory of all issued certificates (X.509 was designed to support the Directory, but it never existed in practice). You will have to contact "all CA" and ask them nicely. Basically, this would mean going to their site, and using the "I lost my password" feature so as to regain control of your account, if it exists. Details vary depending ...


3

Partly solving the underlying problem, you may use Public-Key-Pins header to restrict which certificates are valid for your domain (so a stolen certificate could only be used by a man-in-the-middle would on the first connection to your site). You can also use Public-Key-Pins-Report-Only to get notifications for failed Pin validation. Both headers are ...


3

When only the server sends a certificate, but not the client, the SSL connection is fine and dandy, but the server has no clue about who it is talking too. What SSL provides in that case is that the server can be sure that it talks to the same client all along, with no possible eavesdropper in the middle. If the server must still know who the client may be, ...


2

Microsoft has a "Microsoft Root Certificate Program" here they check the trustworthiness of a certificate authority (CA). If a CA wants their certificate to be automatically updated with Microsoft they need send Microsoft a test certificate so they can test the root certificate. These certificates are then installed by default and updated as they change. ...


2

Browser usually cache intermediate certificates which they've seen once. This can be tested if you use firefox against a server which missing a common intermediate certificate. If the browser has seen this missing certificate already it will allow the connection. But, if you use a fresh firefox profile and retry it will complain, because the certificate ...


2

You can be absolutely sure the traffic doesn't leave your machine, if you use the loopback interface (IP 127.0.0.1) for addressing the server itself. See this question. Communication on the loopback interface doesn't just not leave the machine, it doesn't even enter your network card. It is fully emulated by your OS (at least in linux).


1

As far as I know, it will never leave the machine. If you want to test it by yourself, traceroute is a great tool. Just write traceroute <IP address> and you will be able to see the package route throughout the network. I've just done it with my Macbook and got a single hop as response (indicating that the packet didn't have to leave my machine).


1

First step: forget all about encryption. There is no encryption in certificates. There are digital signatures. Digital signature algorithms, when first invented and published (in the late 1970s), where unfortunately described as "encryption with the private key", which is a flawed analogy, that does not actually work, and entails a heavy dose of confusion. ...


1

PEM means Privacy Enhanced Mail, but the acronym has been long outlived by the file format. The "PEM" format is a method to encode binary data into text, so that the data may survive the transport through a medium which is text-based and not very careful with the data (typically emails). Basically, PEM begins with some header: -----BEGIN FOOBAR----- ...


1

As a rule, encryption provides confidentiality, not integrity. Depending on the algorithm, the attacker may have more or less control on what will show up after decryption. In any case, we are talking here about RSA, in which encryption uses the recipient's public key. As the name suggests, the public key is public (and keeping it "secret" can be hard). ...


1

Speaking about encryption in general, not limiting it to RSA, if a man-in-the-middle modifies an encrypted message, the message will not decrypt as the same message you sent. It really depends on the encryption algorithm used. For example, if a block cipher was used, only the block with the altered data will fail to decrypt properly, the rest of the blocks ...



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