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0

The general problem I see with your solution is that password operations are done on the server, (e.g. the users passwords are passed to the server for checking), however your threat model is to protect the data in the case of a server compromise. If the server is compromised, they can just grab the users passwords as the client submits them for checking. ...


0

Your system is flawed in the first two steps because you're storing the keys with the encrypted data on the same system. If an attacker compromises the server they can just go find the keys and use the keys to decrypt the secret notes. It's difficult to accomplish what you want to do without the users all storing a private key for encryption on their device. ...


2

I think you are missing -servername expired.badssl.com echo "" | /usr/local/ssl/bin/openssl s_client -connect expired.badssl.com:443 -CApath /etc/ssl/certs/ca-certificates.crt -servername expired.badssl.com | /usr/local/ssl/bin/openssl x509 -noout -dates Apparently this server hosts several HTTPS services so the Server Name Indication extension is ...


0

Adding these two lines to my httpd.conf seems to have resolved the issue: AcceptFilter https none AcceptFilter http none The issue ended up not being specific to openssl but it did require the client to hold the connection open. I could create the same situtation using telnet. c:\telnet myserver 80 Would block connections for other users as well


1

I'm not sure to understand very well what you ask, but I will try to give you an answer. First, Firefox is not compatible with AES256-GCM, only with AES128-GCM and with ECDHE key exchange. You can check this by browsing this page with it: https://www.ssllabs.com/ssltest/viewMyClient.html If you want your configuration to work with Firefox, I suggest you to ...


3

This seems to be a bug in Chrome. Root CA Certificates are often still SHA-1 certificates, which is not a security problem (and also not considered a problem by Google: http://googleonlinesecurity.blogspot.ca/2014/09/gradually-sunsetting-sha-1.html), yet Chrome spooks users with the warning - even when the only SHA-1 certificate in the chain is the root CA ...


1

There is no real standard for things in "PEM" format. There was a proposed standard called Privacy-enhanced Electronic Mail, from which the "PEM" acronym was derived; however, that standard never gained traction against its competition (PGP and S/MIME) and nobody implements it. OpenSSL picked up PEM and "enhanced" the PEM format with extra functionalities ...


0

At least do not use the secp112r1, secp112r2, secp128r1, secp128r2, secp160k1, secp160r1, secp160r2, secp192k1 curves. they have a too small size for security application according to NIST recommendation!


0

you can add !EXPORT in place to :!EXPORT40 it will disable all export cipher this link may provide much more information about Freak & Export cipher http://openssl.6102.n7.nabble.com/openssl-users-How-to-disable-all-EXPORT-Ciphers-td56861.html


2

When I do openssl s_client -connect myservername:443 -starttls smtp, other clients are still supported just fine. Of course, the connection from OpenSSL fails: $ openssl s_client -connect myservername:443 -starttls smtp CONNECTED(00000003) didn't found starttls in server response, try anyway... 140029862278800:error:140790E5:SSL routines:SSL23_WRITE:ssl ...


3

ASLR and such things are ways to try to cope with consequences of a buffer overflow -- they are an hide&seek game so that attackers find it harder to turn a buffer overflow into remote code execution. For proper security, it is better to make it so that buffer overflows don't occur in the first place. ... and for that, dynamic linking is better. The ...


4

Here's how I would do that: Examine all the test descriptions from sites like badssl and Qualys SSL Server Test. Follow up on links to the actual issues being tested, read and understand the problems. Run Qualys against your server, capture the traffic using tcpdump, and examine the interactions as much as possible to understand what's going on. Set up ...


1

In the subjectDN field of a certificate, there is the certificate owner distinguished name, which is nominally ordered. Its definition really is a SEQUENCE of SET of name elements, so it is an ordered sequence of unordered sets of elements. It is quite rare to have several name elements in the same set (I have seen it done to put the Common Name, First Name ...


3

You can display Subject Alternative Names (SANs) with OpenSSL like this: (I'm using the Facebook.com cert as an example.) Using the x509 subcommand: $ openssl x509 -in facebook-cert.pem.cer -noout -text | grep 'Subject Alternative Name' -A1 X509v3 Subject Alternative Name: DNS:*.facebook.com, DNS:facebook.com, DNS:*.fb.com, ...


0

This seemed to be the command you want: openssl req -new -x509 -nodes -newkey ec:<(openssl ecparam -name secp384r1) -keyout cert.key -out cert.crt -days 3650


2

The OpenSSH format is unsurprisingly supported by OpenSSH tools. (The OpenSSH public-key format, used in authorized_keys and with a prefix added in known_hosts, isn't itself a "de jure" standard, but is a trivial modification of a public-key encoding within the SSH2 protocol which is standardized.) Less obviously, OpenSSH uses OpenSSL format(s) for private ...


3

From the description, one may infer that the attack works the following way (warning: I wrote "infer" and I mean it -- I have not tried it): The attacker is in position to intercept all network traffic from the victim (e.g. the attacker operates the WiFi access point to which the victim unwisely connected). The attacker owns (legitimately !) some domain, ...


1

What encryption is applied by openssl req when a config is specified? Grepping through the source code it seems to me, that it's either triple DES or nothing. (Regardless of anything that may have been configured in your configuration file.) $ git log apps/req.c | head -n3 commit f1cece554ddf282f1512b4da04664467746ffd24 Author: Richard Levitte ...


1

Use "-brief" You need to use the -brief command line option: $ openssl s_server -accept 443 -cert cacert.pem -key cakey.pem -brief Output: Protocol version: TLSv1.2 Client cipher list: ...


3

If I understood correctly, you think that older versions of OpenSSL are more secure than to newer ones. This is simply not true. Since the Heartbleed vulnerability the project got a lot of attention and that results in a larger number of discoveries / fixes, but those are present in older version as you can see. All versions of the TLS protocol is ...


0

A little step: $ ssh-keygen -y -e -m PKCS8 -f /home/wolf/.ssh/id_rsa | openssl asn1parse 0:d=0 hl=4 l= 290 cons: SEQUENCE 4:d=1 hl=2 l= 13 cons: SEQUENCE 6:d=2 hl=2 l= 9 prim: OBJECT :rsaEncryption 17:d=2 hl=2 l= 0 prim: NULL 19:d=1 hl=4 l= 271 prim: BIT STRING $ openssl rsa ...


0

Server certificates can have multiple chain of trusts (the certificate have multiple roots), and the browser only need to trust one chain to trust the server's certificate. I don't know whether browser actually supports this for client certificates as well. But if they do, you would be able to ship the client certificate signed with two separate root ...


1

On a side note you can use nmap with ssl-enum-ciphers script as follows nmap --script ssl-enum-ciphers -p 443 example.com You will get a response like this. PORT STATE SERVICE 443/tcp open https | ssl-enum-ciphers: | SSLv3: | ciphers: | TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA - strong | TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA - strong | ...


1

I've checked All the websites You've mentioned using an online SHA Checker Tool - https://shachecker.com. As per the result none on this website found with the older SHA-1 algorithms. All seems okay with SHA-2 encryption. This problem might be from Google Chrome or from your MAC device.


15

The server does not send any certificate in the ServerHello message; it sends certificates in the aptly-named Certificate message. As indicated in the standard, the server is supposed to send a complete, ordered chain of certificate, starting with the server's certificate proper, then a certificate for the intermediate CA that issued it, then a certificate ...


3

As Steffen Ullrich has mentioned, you can pass a list of ciphers to the -cipher option of s_client. This is not a single item, but a specification and can also be used for the nginx ssl_ciphers option, or the Apache SSLCipherSuite option. You can pass multiple ciphers using a space, comma or colon separator. Example: openssl s_client -cipher ...


3

While the documentation of OpenSSL lacks a lot, this part is actually well documented. From the man page of s_client: -cipher cipherlist this allows the cipher list sent by the client to be modified. Although the server determines which cipher suite is used it should take the first supported cipher in the list sent by the client. See the ciphers ...


3

It has exactly the same syntax, as eg. SSLCipherSuite configuration setting in Apache, or many similar configuration switches. Example list: ...


3

Instead of setting up multiple CAs, you can just tweak access settings in your Apache configuration. Look at Require directive: http://httpd.apache.org/docs/2.2/mod/core.html#require If you set any authentication requirement, then default Require level is implicitly set to "valid-user" (anyone that meets other requirements). But using Require, optionally ...



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