How to Protect Your Site Forums from Spam postings
From A2Wiki
If your site has an application that allows non-restricted user input through forum posts, comments, contact forms or any other kind of form, your site stands a pretty good chance of attracting unwanted input from spambots. The aim of these malicious programs is often to post advertisements and links for various products and services. Needless to say, this kind of advertising is not something you want on your site.
Here is some general advice on what works to protect your site from these posts:
- Blacklist certain IP addresses
- CAPTCHAs - for more information please see the Wikipedia entry on CAPTCHAs
- Comment Time Interval - don't allow another comment to be posted until after a minimum time interval has passed.
- Deny Duplicate Data - if an identical entry is already in the database, don't allow it to be posted.
- Secure Form Mode -prevent automated scripts (the most common way spam is generated) from repeatedly submitting comments or other form data. A submission is only allowed when a user manually loads a page and submits the form from your site. And once the form data is received, the user has to manually reload the page before they can submit again.
- Site Membership - gives you better control over the people posting on your site. (This works well for preventing spam from getting into our ticket system).
Useful Links:
Six Apart Guide to Comment Spam
