2 Reasons Why Fake User Registrations Are Infiltrating Your Joomla Site

Here is a recent client email related to spam user registrations:

Hi Ogy,

Something a bit odd that I wanted to run by you. When I log onto the Admin site the last week or so there are consistently 3-5 registered users on the site with strange usernames. Generally, most of my customers have usernames similar to their real names.

These ones aren't.

When I look under User Manager at the most recent users, many of them have emails that end in .ru. Is that Russia? Do you think something strange (hacking) might be going on?

What are some reasons why someone would do this evil?

1. post links to scam websites from your Joomla site. When your visitors click on these links, they go to a different website where they are scammed and their information stolen.
2. increase a number of hyperlinks to a particular website using your and other victim websites to boost spam site search engine ranking.

• spambots surf the web, looking for trackbacks, wikis, blogs, forums and other types of web forms to submit information.
• When these automated programs visit your site, they post info and you get it in a form of email notification, new shopper registration, CRM lead entry, comment spam, forum posts, trackbacks, etc.

• protect your forms with captcha. These spambots often use OCR technology to bypass CAPTCHAs but you'll stop most of the spam.
• implement logical questions on forms such as what is 3 + 2? 
• use email validation to prevent unwanted user registrations.
• minimize open forms without any protection.
• complete manual blog comment approvals once per day.

• Spam User Registration ?? at Joomla Forum
• Spambot on Wiki