Justin Parr

<h3>Update: 6/2015</h3>
<p>Changed e-mail token and math problem confirmation logic.  Previously, everything happened all at once, and the user would get prompted mutliple times for the math problem.<br />
Now, the user must answer the math problem first, before the e-mail token is sent.  Once the math problem is correctly answered within the session, it isn’t asked again.  The user must now enter the correct token, which results in successful registration.<br />
SPECIAL THANKS TO OLEG M. FOR HELPING ME IDENTIFY, FIX, AND TEST THE ERROR!!</p>
<h3>Update: 5/2015</h3>
<p>Added E-mail confirmation token.  Prevents registration until user enters a token sent via e-mail.</p>
<h3>Features:</h3>
<ul>
<li>Prevent users from registering, if their IP or e-mail address is listed in the “Comments” blacklist (Settings..Discussion)</li>
<li>E-mails user a 4-digit token, and requires the user to enter the token in order to register.</li>
<li>Users must solve a simple math problem (Add two one-digit numbers).</li>
<li>Places user IP address in “Website” field.</li>
</ul>
<p>This is a super-simple user registration spam countermeasure.  I searched for a plugin that was SIMPLE and EFFECTIVE.  I looked at quite a few plugins that promised the desired effect, but were either cumbersome, or included too many unneeded or unwanted features.  Likewise, there are some very simple plugins that are less-than-effective.</p>
<h3>This plugin is VERY simple:</h3>
<p>If the user’s IP or e-mail address is listed in the “Discussion” comments blacklist, it prevents the user from registering.  This functionality should really be built in to WordPress, so, you’re welcome.</p>
<p>When the user registers, they are presented with a simple math problem – adding a 3-digit number to a 1-digit number.  99% of the “user reg spam” is based on bots being able to attack the basic WordPress registration form.  By adding even a simple math problem, most bots will fail, removing your site as a target of opportunity.  Criminals go after what’s easy – if you make it slightly more difficult for them, they will go after someone else.</p>
<p>Once the user solves the math problem, they are sent a 4 digit token via e-mail, and must enter that token to continue registration.</p>
<p>Finally, knowing the location from where your users register allows you to more effectively evaluate and block the source.  This plugin adds the user’s IP address (at the time of registration)  to the “Website” field.</p>
<p>Go to http://whois.arin.net to find out who they are.  If you decide to block the IP,  add the IP address, part of the IP address, or e-mail domain to the “Discussion” comments blacklist, and ANY user registrations from an IP address matching that pattern will be blocked.</p>
<h3>Configuration</h3>
<h3>To Configure the Plugin:</h3>
<p>NOTE:  NO CONFIGURATION IS REQUIRED.  This plugin is fully-functional using the default values.</p>
<p>In the Plugins page, click “Settings” underneath the “JP User Registration Blacklist” plugin.</p>
<ul>
<li>
<p>Seed:  This value determines how the answer to the math problem is masked.  Periodically change this, to keep the spammers and criminals at bay.  The initial value is randomly-generated.</p>
</li>
<li>
<p>Failed Math Response:  Error message displayed to the user, if they fail to correctly solve the math problem.</p>
</li>
<li>
<p>Rejected IP or E-mail:  Error message displayed to the user, if their IP or e-mail is blocked.  Keep this simple and generic, to keep them from knowing why they are being blocked.</p>
</li>
<li>
<p>Form field name for math problem:  This field name contains the user’s answer to the math problem.  Periodically change this, to keep the bots away.  The initial value is randomly-generated.</p>
</li>
</ul>
<h3>To Block an IP address</h3>
<ol>
<li>In the WordPress Dashboard, go to “Settings…Discuss”</li>
<li>To block all or part of an IP address, add it on its own line to “Comments Blacklist”</li>
<li>To block all or part of an e-mail address, add it on its own line to “Comments Blacklist”</li>
<li>Click “Save”<br />
(For more details, see Examples)</li>
</ol>


JP User Registration Blacklist

Prevent User Registration Spam, and Track New User IP address

Hall

Matt Harrison

TimBHowe

CrossPeak

<p>The Email Blacklist Add-on for Gravity Forms was built to help block submissions from users with generic or competitors email addresses. Prevent the user from processing the form and stop non-qualified leads from being collected.</p>
<p>This plugin allows site admins to create a list of domains that if used in an email field on a Gravity Form it will cause a validation error and block the submission. A default email blacklist and validation message can be created to use across all email fields. These default settings can be overridden on a per email field basis.</p>
<p>Global settings can be added on ‘Forms’ > ‘Settings’ > ‘Email Blacklist’. To add settings to an individual email field, select the field and navigate to the ‘Advanced Settings’ tab.</p>
<p>This plugin works by blocking either individual email addresses (ex. jsmith@gmail.com), email address domains (ex. gmail.com), and/or email address top-level domains (ex. *.com).</p>
<p>Feel free to contribute on <a href="https://github.com/crosspeaksoftware/gravity-forms-email-blacklist" rel="nofollow ugc">github</a>.</p>
<h3>Instructions</h3>
<h3>Global Blacklist Settings</h3>
<p>Once set up, these settings will be used on all email input fields across all the Gravity Forms used on the site. They can be overridden by the individual email blacklist settings below.</p>
<ol>
<li>Once Logged into your site navigate to ‘Forms’ > ‘Settings’ > ‘Email Blacklist’</li>
<li>In the ‘Global Blacklisted Emails’ input enter a comma separated list of blacklisted domains (ie. hotmail.com), email addresses (ie. user@aol.com), and/or include the wildcard notation to block top-level domains (ie. *.com). This setting can be overridden on individual email fields in the advanced settings.</li>
<li>In the ‘Global Validation Message’ input enter a default error message if a blacklisted email is submitted. This setting can be overridden on individual email fields in the advanced settings.</li>
<li>Select the ‘Global Invalid Entry Procedure’ to determine how the blacklisted submissions should be handled, with validation error or collected and marked as spam.</li>
<li>Click the ‘Update Settings’ button to save the settings.</li>
</ol>
<h3>Individual Email Input Blacklist Settings</h3>
<p>Once set up these settings will be used on this form only and in place of the global blacklist settings above.</p>
<ol>
<li>Once Logged into your site navigate to the Gravity Form you would like to update.</li>
<li>Add or update an existing email input field on the form.</li>
<li>Go to the ‘Advanced Settings’ tab for the ‘Blacklisted Emails’ input.</li>
<li>In the ‘Blacklisted Emails’ input enter a comma separated list of blacklisted domains (ie. hotmail.com), email addresses (ie. user@aol.com), and/or include the wildcard notation to block top-level domains (ie. *.com). This will override the globally defined blacklisted emails setting. Enter ‘none’ to bypass the global setting and allow all email addresses.</li>
<li>In the ‘Blacklisted Emails Validation Message’ input enter an error message if a blacklisted email is submitted. This will override the globally defined error message.</li>
<li>Select the ‘Invalid Entry Procedure’ to determine how the blacklisted submissions should be handled, with validation error or collected and marked as spam.</li>
<li>Click the ‘Save Form’ button to save the settings.</li>
</ol>
<h3>Additional Resources</h3>
<ul>
<li><a href="https://docs.gravityforms.com/category/getting-started/" rel="nofollow ugc">Gravity Forms Documentation – Getting Started</a></li>
<li><a href="https://docs.gravityforms.com/email/" rel="nofollow ugc">Gravity Forms Documentation – Email Input Fields</a></li>
<li><a href="https://docs.gravityforms.com/spam/" rel="nofollow ugc">Gravity Forms Documentation – Fighting Spam</a></li>
</ul>


Gravity Forms Email Blacklist

Exactly what I needed - works like a charm.

Thanks @cleverpixel

Brilliant

Add-on for Gravity Forms to create a Blacklisting of specific emails or domains for the Email input field to throw a validation error or mark as spam.

JP User Registration Blacklist vs Gravity Forms Email Blacklist