$Text = preg_replace('#<([^>]*?)(src)="(?!http|redir)(.*?)"(.*?)>#ism', '<$1$2=""$4 class="invalid-src" title="' . t('Invalid source protocol') . '">', $Text);
// sanitize href attributes (only whitelisted protocols URLs)
- $allowed_link_protocols = Config::get('system', 'allowed_link_protocols', array());
+ // default value for backward compatibility
+ $allowed_link_protocols = Config::get('system', 'allowed_link_protocols', array('ftp', 'mailto', 'gopher', 'cid'));
- // Always allowed protocol even if config isn't set
+ // Always allowed protocol even if config isn't set or not including it
$allowed_link_protocols[] = 'http';
$regex = '#<([^>]*?)(href)="(?!' . implode('|', $allowed_link_protocols) . ')(.*?)"(.*?)>#ism';