The Spam and Open Relay Blocking System (SORBS), a long-time source of information on known sources of spam, widely used to create blocklists, has been shut down by its owner, cyber security software vendor Proofpoint. SORBS provided free access to a DNS-based Block List (DNSBL) that lists over 12 million host servers known to disseminate spam, phishing attacks and other email nasties. The service states its list "typically includes email servers suspected of sending or relaying spam, servers
