The Spam and Open Relay Blocking System

Status:	Active
Website:	www.sorbs.net
Removal:	www.sorbs.net/overview.shtml

The SORBS (Spam and Open Relay Blocking System) provides free access to its DNS-based Block List (DNSBL) to effectively block email from more than 12 million host servers known to disseminate spam, phishing attacks and other forms of malicious email. The list typically includes email servers suspected of sending or relaying spam, servers that have been hacked and hijacked, and those with Trojan infestations. In an attempt to provide preemptive protection, SORBS also lists servers with dynamically allocated IP addresses. SORBS maintains 17 distinct DNSBL zones.

Listing Policy

A zombie machine is a computer or server that is no longer full controlled by it’s original owner. It may appear on the surface to be operational, and even secure, however, underneath that facade is a compromised system of malicious software. The infected machine could be as simple as a remotely controlled open relay, to as sophisticated as a single node that is part of a multi thousand farm of botnets. zombie.dnsbl.sorbs.net contains all known cases of machines that have been compromised in some way.