CBL Mail Filter is an advanced mail filter service primarily used to combat contact form SPAM. A high proportion of SPAM comes from other countries known as Foreign SPAM.
Foreign SPAMMERS use contact forms to send melicious and annoying emails and while there are plugin which combat this, there is no silver bullet solution. This plugin allows you to filter all mail based on the country of where the spammers are connecting to your site. For instance, if you provide services in Australia only, you can configure this plugin to anly allow visitors from Australia to post in contact forms.
The plugin allows to to configure a comma separated list of two-character ISO 3166-1 country codes. So you can specify multiple countries. In addition to the standard country codes, you can also use:
- A1 – an anonymous proxy
- A2 – a satellite provider
- EU – an IP in a block used by multiple European countries
- AP – an IP in a block used by multiple Asia/Pacific region countries
The plugin is very lite-weight as it offlods the processing to a thrid party server that processes the IP address of the visitor who is submitting a form. It uses a database of IP addresses supplied by MaxMind . MaxMind is a leading provider of IP intelligence and online fraud prevention tools with a reported accuracy of 99.8%. Based on your configuration it will allow the email to be sent, or it will reject it.
- AU,NZ Only allows visitors from Australia and New Zealand to send mail
- AP – Only allows visitors from Asia/Pacific region countries to send mail
Once the plugin is installed visit Settings -> CBL Mail Filter to configure it.