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1

I use the -subj modifier to add alternate dns on command line. Example below for a self signed x509 certificate : openssl req \ -x509 \ -batch \ -nodes \ -sha256 \ -days 3650 \ -newkey rsa:2048 \ -keyout selfsigned.key \ -out selfsigned.crt \ -subj "/C=FR/ST=Ile de ...


1

The reason AES-CBC isn't an authenticated mode has everything to do with the CBC and nothing to do with the AES. CAST5-CBC isn't inherently authenticated either; changing one bit in the IV changes the corresponding bit in the first block, and there's no way to detect it, because that's a result of the CBC construction and not of the cipher.


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You're running a version of OpenSSL provided by your Linux distribution. They will provide an update incorporating those security fixes, backported to the version you currently have. All you need to do is to install the updates (e.g. yum update) when they become available.


1

Yes. You should always run the latest version of code (assuming it doesn't break a critical system supported by an earlier version, in which case... good luck!).


2

the first security hole is your shared "el-cheapo" server. if you can not trust your machine, you can not trust your applications. what this means is that if you have no controle over the machine itself, adding security to it is pointless, an attacker will just attack your webserver instead of your connection and makes sure he can do anything he/she wants ...


1

If you are using a simple passphrase-based approach, then your encryption is at most as secure as your passphrase. And even if you are using a long passphrase, your encryption is at most as secure as the key derivation function used to get from the passphrase to the actual key. Openssl uses a simple MD5 hash to generate the key, which has two drawbacks: It ...


4

OpenSSH is unaffected by FREAK for several reasons: It only uses a small, carefully-audited portion of the OpenSSL library. The SSL cipher-negotiation code is not one of the parts it uses. The SSH protocol is resistant to "downgrade" attacks: the size of the server key is fixed at the time of key generation and the key fingerprint is stored by the client. ...


10

The confusion comes from the way OpenSSL words its configuration options. In the protocol, there are two very distinct things: The protocol version. This can be SSL 3.0, TLS 1.0, TLS 1.1 or TLS 1.2 (or something else, not yet defined). Internally, the version is encoded as a 16-bit integer of value 0x0300, 0x0301, 0x0302 or 0x0303, respectively (so TLS ...


2

Because they are different things, the protocol is about how to handle the handshake and such, the cipher list is about which ciphers you are willing to accept for your connections. If you disable the protocol, you won't be able to talk with a server that only support this protocol. If you disable the ciphers, you'll be able to start the handshake but you ...


0

Only the original 40-bit EXPORT ciphers are affected by the attack anyway. It is unfortunate that OpenSSL disabled the 56-bit EXPORT1024 ciphers back in 2006. And yes these are the only two categories of EXPORT ciphers in SSl/TLS.


1

Updated Answer: According to: https://groups.google.com/forum/#!msg/mailing.openssl.users/hGggWxfrZbA/unBfGlsfXyoJ the gcm support is currently broken in v1.0.1f (what Ubuntu currently uses). There should be patches out for Version v1.0.1.g which then should have a workable GCM mode. However, currently I would just stick with the CBC mode, as for key ...


3

The RSA "export" cipher suites can work a bit like ephemeral Diffie-Hellman: if the server's "permanent" key is longer than 512 bits, then the server is supposed to generate a new one (dynamically) of length 512 bits, and send it over the wire as a ServerKeyExchange message, signed with its permanent private key. See section 7.4.3 of RFC 2246. The private ...


0

1) Cool names count. Don't discount the value of public relations. 2) Heartbleed, BEAST, CRIME, and POODLE all impacted (or could be be reached through) web servers. Web servers tend to be publicly available, widespread, and directly identified (in the minds of the press and non-technical public) as "THE INTERNET." Therefore, these issues had a wider ...


1

The process for assigning a CVE's CVSS score to a vulnerability is very prescriptive. There is little room for interpretation, or to account for impacts which the are not accounted for by the scoring formula. So, in the end some relatively major issues will end up with oddly low scores, and some relatively trivial issues will end up with excessively high ...


4

Some implementations of TLS 1.0 did not properly validate the padding as required by the TLS specification. This led to a situation in which the POODLE bug could be leveraged against TLS 1.0, despite the fact that it should be secure against the attack. Later versions of TLS (i.e. 1.1 and 1.2) are inherently secure against POODLE and other padding oracle ...


1

Just dredging up an old question. I recently had need to create a DH cert for test purposes. This is how to do it. First create DH parameters and private key as per Tom's answer: openssl dhparam -out dhparam.pem 1024 openssl genpkey -paramfile dhparam.pem -out dhkey.pem Next create the public key file: openssl pkey -in dhkey.pem -pubout -out dhpubkey.pem ...



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