Increasing Spam Threat from Proxy Hijackers

Spamhaus reports a surge in spam driven by stealth 'proxy spamware' which compromises broadband PCs and instructs them to send mail through ISP mail relays, resulting in 75–90% of incoming spam at major providers and posing a risk of email delivery overload; recommended defenses include throttling outbound mail, separating SMTP servers, and requiring SMTP-AUTH.