User Registration Spam is becoming an important concern for many of the WordPress membership site owners. If your WordPress site is set to allow user registration, then it’s probably vulnerable to user registration spam from spam-bots. It wlll create a serious spam concern for hosting server, necessary steps has to be taken to ensure that SPAM is avoided at any cost.
As a newbie to WordPress, i had challenges combating with spam registration due to the fact that i set registration open.
I had to go through the stress of deleting 500+ spam users everyday.
If you’re experiencing similar situation, below are Top Six(6) WordPress plugins to help stop spam registration
  1. Sabre
    Sabre is an acronym for Simple Anti Bot Registration Engine. It’s a set of counter measures against spam registration on your blog.

    Your visitors are granted permission to register freely on your blog and now you are plagued by fake users automatically created by spammers? Sabre is the solution to stop definitely these robotized visitors.
    List of available features are: Inclusion of a captcha in the registration form, Selection of the captcha’s complexity, Selection of the background colour for the captcha image, Inclusion of a math test in the registration form, Selection of the math test’s complexity, Inclusion of a text test in the registration form, Random or fixed choice of the test to run, Unobstrusive tests to detect if registration is done by humans or not, Registration blocked if Javascript is unsupported by the browser, Registration blocked if visitor’s IP address is found on ban lists, The user can validate his registration by clicking on a link sent by mail, Limited number of days for user confirmation (Without being confirmed within the period of time, the user account is disabled (monosite only), Log on prohibited before user confirmation, User is allowed to choose his password when registering on the site, User must agree with a warning text, disclaimer or general policy note, when registering User must give an invitation code during registration, Main statistics displayed on the site’s dashboard, Custom logo on logon/ registration screen.
  2. Wanguard
    This plugin is very good at stoping spam registration and making your database clean. Upon user registration, WangGuard will check against a centralized database if the user is a Splogger or spam-user.

    If WangGuard determines that the user is a Splogger, WangGuard won’t allow the registration on your site. No need to put any kind of filter in the user registration page (eg captcha).
    This is the greatness of WangGuard, not hinder users who wish to register on your site with Captchas and other things that just makes the registration being more difficult and in many cases do not stop Sploggers. But in case you want to put something WangGuard gives you the ability to add one or more security questions from the plugin’s administration page, which will be randomly displayed on the registration page.
  3. Stop Spammers Registration Plugin
    This plugin uses 15 different strategies to block spammers. Eliminates 99% of spam registrations and comments.

    Checks all attempts to leave spam against, ProjectHoneypot, BotScout, DNSBL lists such as, known spammer hosts such as Ubiquity Servers, disposable email addresses, very long email address and names, and HTTP_ACCEPT header.
    Checks for robots that hit your site too fast, and puts a fake comment and login screen where only spammers will find them.
  4. ProfilePress
    This plugin has a feature that let you modify the registration link of your WordPress website. This will result in greatly reduced spam registrations.

    The default registration link is “wp-login.php?action=register” and is heavily targeted by spam- bots.
    >This plugin create a custom registration form for you and redirect the default registration page to the custom page.
  5. Confident Captcha
    Confident CAPTCHA™ is a clickable, picture CAPTCHA that stops spam and malicious bots, while remaining very easy for people to solve. All your website visitors have to do is click a few specific pictures to prove they are human and not a bot.

    It takes just a few seconds to solve.
  6. Growmap Anti Spambot Plugin
    This plugin will add a client side generated checkbox to your comment form asking users to confirm that they are not a spammer.

    It is a lot less trouble to click a box than it is to enter a captcha and because the box is genereated via client side javascript that bots cannot see, it should stop 99% of all automated spam bots.
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