Alex Mills

When it comes to spam and <a href="https://codex.wordpress.org/Introduction_to_Blogging#Pingbacks" rel="nofollow ugc">pingbacks</a>/<a href="https://codex.wordpress.org/Introduction_to_Blogging#Trackbacks" rel="nofollow ugc">trackbacks</a>, the vast majority by far is via trackbacks rather than pingbacks. Very, very few people use trackbacks for legitimate uses anymore (I’ve gotten less than 5 in the last 8 months) as WordPress, etc. all use pingbacks now as their primary ping method.
I had already installed <a href="http://ocaoimh.ie/cookies-for-comments/" rel="nofollow ugc">Cookies For Comments</a> which successfully stops most spam comments but I still had to deal with the tons of trackback spam. So, I wrote this plugin.
It will disable new trackbacks across your site, both legitimate and spam. However since very few people use trackbacks legitimately, this combined with Cookies For Comments should cut your spam down to next to zero.
Why should I use this plugin over one of those trackback validator plugins?
Most non-Akismet style anti-trackback spam plugins work by connecting to the URL that sent the trackback and looking for a link to your blog. The problem with this is that many spammers actually post links to your blog in their spam posts rendering those types of plugins useless. Even those that check the IP address to make sure it matches are beaten by spam blogs (aka splogs).
In the end it’s up to you what to use for anti-spam, but I personally use Cookies For Comments, this plugin, and then Akismet to catch anything that makes it through.

Disable Trackbacks

Globally disables trackbacks to cut down on spam. Very, very few people legitimately use trackbacks and spammers love them, so it's worthy tradeo …

szehau

Default Trackbacks is a wordpress plugin that sends trackback to the preset URLs. It is enhanced version of the old Default Trackback.
Features:
<ul>
<li>Send trackback to the URLs in the list when a post status is changed from “any” to “publish”.</li>
<li>Configure the trackback URLs under WordPress?s admin setting page.</li>
<li>Default setting for sending trackbacks (to send trackbacks by default or not each time publish a post).</li>
<li>Option to override default setting above at edit/new post page.</li>
</ul>

Default Trackbacks

This plugin will send trackbacks to URLs in the list ONLY when user publish a post or change the post status to publish.

Disable Trackbacks vs Default Trackbacks