Block Comment Spam Bots for WordPress

Bypassing the comment form by posting directly (via CURL or WGET commands), is quite easy. Just send the post ID number, and the bot’s fake name and email, and the spammy content. Boom! Comment spam is on your site!

The result is comment spam – and that is not always caught by other comment spam checkers. Even if it is caught by programs such as Akismet, processing that spam takes some server resources, including writing to the database.

This plugin uses several techniques to ‘sense’ a spambot. There are hidden fields that are changed after a delay. There is a delay in displaying the submit button. And it blocks direct access to the WordPress post/processing functions.

The techniques, also used in our standalone “FormSpemmerTrap” (FST) program, and our other anti-spam plugins (like FormSpammerTrap for Comments), are very effective. They use a bit of JavaScript to block spambots – since automated processes via CURL/WGET/etc cannot process JS code.

It’s simple: you install this plugin, activate it, and bot comments will stop. Immediately.

And it doesn’t add any visual impediments to your comments. No reCaptcha things (which many see as a pain). No silly questions (‘what is 2+8’) on the form. Your comment form does not change. Regular users will not notice a difference. But you will. No more spam comments for you!

This is the best solution to block comment spam. We’ve tested it on a site that had 20-40 spam comments a day. With this plugin enabled, the spam comment stopped. Immediately. And there have been none since installing this plugin. Not one. Zero.

The Admin, Comments list page is modified to show a column with a green checkmark icon if the comment was entered by a real person and not a bot. This is an assurance that the comment was not entered via an automated CURL/WGET to the wp-comments-post.php file. A comment that is on the list that does not show the checkmark was done by a bot. But you won’t see those blocked comments with this plugin enabled. They never get into your database. You can hover over the checkmark icon to see the GUID value indicating a person entered the comment.

The plugins ‘Settings’ screen has no settings. You don’t even need to look at the Settings screen. If you do, you’ll see information about the plugin. And there is a CURL command you can use to test the effectiveness of blocking (or not blocking) direct access to the wp-comments-post.php file.

The plugin also adds the hidden GUID field to the comment form after a delay to help block bots that are using the comment form to submit. If the hidden field is not submitted then a bot tried to bypass the comment form. And a short delay happens before the comment submit button is displayed – another bot protection.