Chema

Email Validator is a FREE lightweight and high-performance WordPress plugin that provides real-time email address validation during registration and form submissions on your website. It efficiently detects disposable email addresses and guarantees that only valid email addresses are accepted, enhancing the integrity of your user data.
<h3>Features</h3>
<ul>
<li>Validates email addresses in real-time.</li>
<li>Prevents registration with disposable email addresses.</li>
<li>Checks for valid email format using RFC 822.</li>
<li>Verifies DNS MX records for email domains.</li>
</ul>
<h3>Usage</h3>
Email validation is automatically applied during user registration and other form submissions. If an invalid or disposable email address is entered, users will be notified of the issue and asked to provide a valid email address.Email Validator is free software distributed under the terms of the GNU General Public License. For more information, visit <a href="https://www.gnu.org/licenses/gpl-3.0.html" rel="nofollow ugc">the official GPL page</a>.
Uses https://github.com/ivolo/disposable-email-domains/ to get an updated list of disposable email domains.
For support and feedback, please visit the <a href="https://wordpress.org/plugins/email-validator/" rel="ugc">plugin page on WordPress.org</a>.

Better Email Validator

Email Validator is a FREE lightweight and high-performance WordPress plugin that provides real-time email address validation during registration and f …

Tobiask

Simple Trackback Validation Plugin performs a simple but very effective test on all incoming trackbacks in order to stop trackback spam. Now with topsy.com blocker.
How it works:
When a trackback is received, this plugin
<ol>
<li>
checks for topsy.com trackbacks and marks this as spam.
</li>
<li>
checks if the IP address of the trackback sender is equal to the IP address of the webserver the trackback URL is referring to. This reveals almost every spam trackback (more than 99%) since spammers do usually use bots which are not running on the machine of their customers.
</li>
<li>
retrieves the web page located at the URL included in the trackback. If the page doesn’t a link to your blog, the trackback is considered to be spam. Since most trackback spammers do not set up custom web pages linking to the blogs they attack, this simple test will quickly reveal illegitimate trackbacks. Also, bloggers can be stopped abusing trackback by sending trackbacks with their blog software or webservices without having a link to the post.
</li>
</ol>
There are several options available and you also can enable logging to get all actions, which are performed by the plugin, logged. Also, you can select how to treat spam trackbacks (do not save in the database or mark as spam or place into moderation) and several other stuff.
Please visit <a href="http://sjmp.de/blogging/simple-trackback-validation-with-topsy-blocker/" title="Simple Trackback Validation with Topsy Blocker" rel="nofollow ugc">the official website</a> for further details and the latest information on this plugin.

Simple Trackback Validation with Topsy Blocker

REPLACEMENT of the original Simple Trackback Validation Plugin from Miachel. Performs a simple but very effective test on all incoming trackbacks in o …

Better Email Validator vs Simple Trackback Validation with Topsy Blocker