andreyk

The plugin increases security of a site in case it has no SSL certificate, 
useful for owners of small sites who want to secure their passwords and 
other posted data but don’t want to buy SSL certificate for each domain 
and subdomain: it protects from sniffering the most important data such as 
passwords when they are being sent from forms of your site to the server.
When the form served by the plugin is submitted all input data are being 
joined into a string, then this string is being encrypted with AES algorythm 
by disposable key and only encrypred string will be sent.
A browser encrypts the disposable key in javascript by the RSA public key 
and sends it to the server; then the server decrypts it with the RSA private 
key and then use it to decrypt the posted data with AES.
Translations included: Ukrainian, Russian, German and Brazilian Portuguese.
I just adapted usage in WordPress the jCryption jQuery plugin, v. 3.1.0. 
Please check www.jcryption.org to learn how jCryption works.

WP jCryption Security

Prevents forms data against sniffing network traffic through encryption provided by jCryption javascript library.

PascalBajorat

This plugin provides a function for automatic email encryption and a shortcode for manual settings. It will help you to protect every email address on your website against spam.
Simply enable the automatic protection mode and you are safe.
<blockquote>
<h4>MailCrypt Shortcode:</h4>
<code>[mailcrypt email="name@example.com" href="Alternative Contact Page URL" title="A-Tag title Attribute"]</code>
<ul>
<li>email = required</li>
<li>href = optional</li>
<li>title = optional</li>
</ul>
Change the link text with an enclosing shortcode: 
 <code>[mailcrypt email="name@example.com" href="Alternative URL"]link text[/mailcrypt]</code>
</blockquote>
You can also use a shorter variant of [mailcrypt] -> [mail]
It’s also possible to use PB MailCrypt in an automatic mode, you can enable this feature under “settings > general”.
New: Now supports Advanced Custom Fields.
If you have any questions or problems, you can ask me: <a href="https://www.bajorat-media.com/" title="Pascal Bajorat - Webdesigner / WordPress / WebDeveloper Berlin" rel="nofollow ugc">Pascal Bajorat – Webdesigner / WordPress / WebDeveloper</a>
<h3>License</h3>
GNU General Public License v.3 – http://www.gnu.org/licenses/gpl-3.0.html

PB MailCrypt – AntiSpam Email Encryption

This Plugin provides functions for an automatic email encryption and protection against spam.

WP jCryption Security vs PB MailCrypt – AntiSpam Email Encryption