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Encrypting the Net: Use "Let’s Encrypt" SSL to Set Up Secure Website Traffic

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By: Krintoxi

February 1, 2016

Encrypting the Net: Using "Let’s Encrypt" SSL to Set Up Secure Website Traffic - CybraryHello,This guide comes out of inspiration from the Course offered here not too long ago: SSL Traffic: The Cyber Criminal’s Best Friend Instructed By Darrin Coulson. I'll start with a bit of basic background knowledge you should have on what SSL (Secure Sockets Layer) Encryption is, and how it benefits us.SSL (Secure Sockets Layer) is a basic security protocol for establishing an encrypted link between a web server and a client.With a normal web connection, an attacker is able to intercept all data being sent between a browser and a web server. They can see and use that information how they like, because it's transmitted in Plain Text.Please keep in mind that all browsers have the capability to interact with secured web servers using the SSL protocol. However, the browser and the server need what's called an "SSL Certificate" to be able to establish a secure connection. How the process goes:
  1. Browser connects to a web server (website) secured with SSL (HTTPS). Browser requests that the server identify itself.
  2. Server sends a copy of its SSL Certificate, including the server’s public key.
  3. Browser checks the certificate root against a list of trusted CAs and ensures the certificate is unexpired, unrevoked, and that its common name is valid for the website it's connecting to. If the browser trusts the certificate, it creates, encrypts and sends back a symmetric session key using the server’s public key.
  4. Server decrypts the symmetric session key using its private key and sends back an acknowledgement, encrypted with the session key to start the encrypted session.
  5. Server and Browser now encrypt all transmitted data with the session key.
 Why SSL is so important?SSL is essential in protecting data from being spied upon by someone else on the internet because they will not be able to understand the encrypted data.When you type a search into or, it's not very hard for someone to eavesdrop on the phrase you're searching for. Similarly, when you log into Facebook, it's not difficult to intercept and decipher your password while it's in transit between your computer and Facebook’s servers. And, when you send payment information to PayPal, a hacker cannot listen in and swipe your credit card number.SSL helps do away with Man-In-The-Middle Attacks. But, as everyone who has tried to get and maintain a certificate for a web server before will tell you, it's no easy task. Here's where Let's Encrypt comes in Let’s Encrypt automates every single step: from no validation emails, to no complicated configuration editing, to no expired certificates breaking your website. And, of course, because Let’s Encrypt provides certificates for free, there's no need to arrange payment.
1 $ git clone $ cd letsencrypt3 $ ./letsencrypt-auto --help
 The Let's Encrypt script will install all of its own dependencies and updates client code automatically.If you’re running Apache on Debian-based Operating System, you can try the Apache plugin included, which automates both obtaining and installing the SSL certs:

./letsencrypt-auto --apache

To get a cert using the “webroot” plugin, which works with the webroot (www) directory of any webserver software:

./letsencrypt-auto certonly --webroot -w /var/www/example -d

The this will obtain a single cert for,,, and; it will place files below /var/www/example to prove control of the domain. After doing this , you'll have to configure your web server to use the SLL Certificate you have just created. To do this:

edit the: httpd-ssl.conf Apache configuration file.

To locate this file on your server, open a Terminal , and type:

Locate httpd-ssl.connf

Inside this file, you'll need to create a virtual host configured to use port 443 (which needs to be port forwarded, if on your own connection)

<VirtualHost *:443>

 #   General setup for the virtual host

DocumentRoot "/opt/lampp/htdocs/"



ErrorLog "/opt/lampp/logs/error_log"

TransferLog "/opt/lampp/logs/access_log"

#   SSL Engine Switch:#   Enable/Disable SSL for this virtual host#   SSLEngine on#   Server Certificate:#   Point SSLCertificateFile at a PEM encoded certificate.  If#   the certificate is encrypted, then you will be prompted for a#   pass phrase.  Note that a kill -HUP will prompt again.  Keep#   in mind that if you have both an RSA and a DSA certificate, you#   can configure both in parallel (to also allow the use of DSA#   ciphers, etc.)#   Some ECC cipher suites (   require an ECC certificate, which can also be configured in#   parallel.

SSLCertificateFile "/etc/letsencrypt/live/"

SSLCertificateKeyFile "/etc/letsencrypt/live/"

SSLCertificateChainFile "/etc/letsencrypt/live/"

#SSLOptions +FakeBasicAuth +ExportCertData +StrictRequire

<FilesMatch ".(cgi|shtml|phtml|php)$">

SSLOptions +StdEnvVars



-----------------------------------------Make sure you edit the following accordingly. This tells Apache where to look for the Certification that Let's encrypt created:

SSLCertificateFile "/etc/letsencrypt/live/"

SSLCertificateKeyFile "/etc/letsencrypt/live/"

SSLCertificateChainFile "/etc/letsencrypt/live/"

 Once you have your web server configured, close the file and restart the server.Now, you should be able to visit your domain on it's encrypted port 443:https://example.comAn SSL Certificate from Let's Encrypt looks something like this:
With this, I hope I was able to help some of you out there trying to Encrypt your Servers connection. Thank you.I also want to take the opportunity to thank @trevorh for helping me out with submitting this and getting my issues with OP3N resolved."Conformity is the jailer of freedom and the enemy of growth."
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