Posts Tagged ‘forum category’

How to reduce spam in PHPBB based internet forum on Debian GNU / Linux

Monday, March 26th, 2012

phpbb reduce spam bot registrations on Debian Linux tiny script

I had to install two PHPBB based internet forums, some long time ago. Since long time passed and I haven't checked what's happening with them I just noticed. They start filling up spam threads. The phpbb installations are done using the standard shipped deb packages in Debian Linux Lenny.

After checking online, I found one smart solution to . The idea is very simple most spam bots are written in a way that they don't have a properly set timezone. Therefore the quickest way to get rid of spam bots which try to auto register and put spam content inside the a forum category or post is to add a simple if condition in php to check the browser set timezone:

The file to add the php if condition is ucp_register.phpThe phpbb package install places default phpbb path on Debian is /usr/share/phpbb3/ and hence the file I had to modify is located in:

/usr/share/phpbb3/www/includes/ucp/ucp_register.php

To make the TZ check one needs to modify ../www/includes/ucp/ucp_register.php and look for php array definition:

$data = array(
'username' => utf8_normalize_nfc(request_var('username', '', true)),
'new_password' => request_var('new_password', '', true),
'password_confirm' => request_var('password_confirm', '', true),
'email' => strtolower(request_var('email', '')),
'email_confirm' => strtolower(request_var('email_confirm', '')),
'confirm_code' => request_var('confirm_code', ''),
'lang' => basename(request_var('lang', $user->lang_name)),
'tz' => request_var('tz', (float) $timezone),
);

Right after this chunk of code add the if condition code which is like so:

if ($data['tz'] == '-12.00')
{
die('Die, bot! Die.');
}

From now onwards, any attempt for new user registration with an incorrect timezone of -12.00 will be immediately stopped while the forum spammer bot will be offered an empty page 🙂

Another good practice is to disable Birthday Listing from phpbb Admin Control panel (ACP). Go to menus:

ACP -> General -> Board Settings -> Enable Birthday listing: (No)

Enable birthday listing phpbb forum screenshot

I like disabling birthday listing, as when it is enabled and you have some spammer registrations, which even though didn't succeeded to contaminate your forum content has specified a birthday and therefore there profiles gets popping up each different day on the main page of the forum.
This will not eradicate all spammer bots, but at least will significantly decrease spammer bot registrations.