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1

And that the Heartbleed bug is most vulnerable from TLS 1.1. and TLS 1.2 and NOT from TLS 1.0. It might be that your admin mixed up some facts: It is true, that Heartbleed is in a way connected to TLS 1.1 and TLS 1.2. But the connection is only, that the OpenSSL release 1.0.1 not only added support for TLS 1.1 and TLS 1.2 but also introduced support for ...


13

Your admin got it real wrong (or there was some translation mishap). TLS 1.1 and 1.2 fix some issues in TLS 1.0 (namely, predictability of IV for CBC encryption of records). It is possible to work around this issue in TLS 1.0, but it depends on how hard the implementations work at it. So, in that sense, TLS 1.1 and 1.2 are more secure than TLS 1.0, since ...


2

Whoever told you this probably doesn't quite get what Heartbleed is about: it's an implementation-specific vulnerability (in some versions of OpenSSL), it's not really related to the version of SSL/TLS. From http://heartbleed.com/: The vulnerable versions have been out there for over two years now and they have been rapidly adopted by modern operating ...


3

TLS 1.0 TLS 1.0 was an upgrade from SSL 3.0 and the differences were not dramatic, but they are significant enough that SSL 3.0 and TLS 1.0 don't interoperate. Some of the major differences between SSL 3.0 and TLS 1.0 are: Key derivation functions are different MACs are different - SSL 3.0 uses a modification of an early HMAC while TLS 1.0 uses HMAC. The ...


0

You can use https://www.ssl2buy.com/wiki/ssl-installation-checker/ to verify SSL certificate installation.


0

I just wanted to point/link to something that I find very useful. This page, on top of providing a very good explanation of some of the warnings we do get using SSL Test from SSL Labs (they do the same), also provides Windows powershell snippets (or the full script) that will help you getting a better configuration in case you are using Windows in the ...


6

Use SSL Labs For a first test, run the URL through SSL Labs: (be sure to check the "Do not show the results on the boards" checkbox) https://www.ssllabs.com/ssltest/ This will tell you if the certificate is correctly installed when looking at it from the outside. Now concerning the "keystore alias": That is only visible from inside the server. So you ...


0

My solution was to pass subjectAltName via an environment variable. First have this added to openssl.conf: [ san_env ] subjectAltName=${ENV::SAN} Then set the environment variable before invoking openssl: export SAN=DNS:value1,DNS:value2 openssl req -extensions san_env -subj '/CN=value1' ... Note: the -extensions san_env parameter needs to be present ...


-3

If you can't make it, just fake it. ;-) http://www.code-wizards.com/projects/libfaketime/ libfaketime (FakeTime Preload Library) - report faked system time to programs without having to change the system-wide time By faking the system time you can set "Not Before" to any value you like.


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 ...


42

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 ...


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.


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.


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 ...


1

Come to think of it, you could implement an engine with a weak RNG and insert it into OpenSSL using: ENGINE_set_default(e, ENGINE_METHOD_RAND); That should make sure that the random number generator is used. Of course it may be a good idea to ignore any seed information given to the random RNG by the OpenSSL. This has the obvious disadvantage that it may ...


1

Although there are no guarantees, there are mathematical safety-measures against poor keys due to inappropriate random number generators. You could for example try some nice software tools to test the statistical entropy that your generator puts out: Dieharder TestU01 These tools come with a large number of statistical tests, but as RFC 4086 states: ...


0

Answering my own question, as I can't find this documented anywhere. The problem here is that the OpenSSL build bundled with OS X doesn't come compiled with CMS supported. In order to enable CMS support you will have to compile your own version of OpenSSL. First, clone the OpenSSL Github mirror: git clone git@github.com:openssl/openssl.git Checkout a ...


0

The operation phase is fine. HTTPS should protect against MITM attacks in the operational phase. Signing of the data is fully acceptable in the operational phase. The installation phase is fine, although I suspect that you meant HTTP instead of HTTPS. This will work and the MAC's will protect from tampering. What I'm now proposing is a "could be". You ...


3

From your description at this query at stackoverflow I get the information, that all customers will use their browsers to contact these sellers. When you only use self-signed certificates or use your own CA for the sellers each of these customers must explicitly add an exception (or your CA) to their browser. And of course they should not just trust ...


3

I haven't tested OpenSSL but I'm pretty sure it implements AES-CBC correctly. Your program, however, obviously uses different data, so it isn't surprising that you get different results. The test vectors are given out in hexadecimal. For example KEY = 0000000000000000000000000000000000000000000000000000000000000000 IV = 00000000000000000000000000000000 ...


0

By default the des program encodes the output as base64, so you need to decode that before passing to the decryption algorithm, OpenSSL provides the -a option to encode / decode base64. The input to the DES decryption should start with the string “Salted__” if the input is base64 then this translates into “U2FsdGVkX18… “ at the beginning of the file.



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