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Get ciphers with nmap

Good cipher usage is important for the encryption of you connection. With nmap we can look at them and harden the config where needed. For that we use the nmap scripting engine with ssl-enum-ciphers script.

Test and install nmap

First, check if namp is installed.

sebastian@nw4mac:~$ nmap -V

Nmap version 7.40 ( https://nmap.org )
Platform: x86_64-apple-darwin16.3.0
Compiled with: liblua-5.3.3 openssl-1.0.2j nmap-libpcre-7.6 libpcap-1.8.1 nmap-libdnet-1.12 ipv6
Compiled without:
Available nsock engines: kqueue poll select

If it is not installed, install it!

# Debian / Ubuntu
apt install nmap

# Apple macOS
brew install nmap

# CentOS / Redhad / Fedora
dnf install nmap
# or with yum
yum install nmap

Get your ciphers

When the installaton is done, run your first scan. Use -p for the port number and choose your own target.

nmap --script ssl-enum-ciphers -p 443 www.binaryfigments.com

And see the results in the window below. It also gives a grade on you cipher usage. An A grade is nice to have!

You can also chech the ciphers on you e-mail server in port 993 for IMAP of port 587 for SMTP with TLS.

nmap --script ssl-enum-ciphers -p 587 mail.solarisinternetgroep.nl

Wich give the following result:

The scores above are fine, but what is you have some issues in your cipher configuration on your websiter. Your grade will be lower like a C of D. If that is the case, you really should look at your webserver configuration and turn of the bad ciphers!

More than a portscanner

In these examples you can see that nmap is more than only a port and network scanner. It can do so much more with the scripting engine. Later more about the nmap scripting engine! In the meanwhile, read about it over here: https://nmap.org/book/man-nse.html.


2017-04-22 2 minuten leestijd Sebastian ciphers security ssl tls nmap ciphers security ssl tls nmap