What is SURBL?
SURBLs differ from most other lists in that they're used to detect unsolicited messages based on message body URIs (usually web sites). Unlike most other lists, SURBLs are not meant to identify messages senders by their message headers or connection IP addresses. Instead they help identify messages by the sites mentioned in their message bodies.
Some results of using SURBLs appear in the News section. Detection rates are around 80 to 90%, with false positive rates of the different lists ranging from about 0.001 to 0.05%. We continually work to improve both the detection and false positive rates in a variety of ways. Descriptions of the different SURBL lists and their data sources can be found in the Lists section.
SURBL SURBLs are often used in conjunction with other conventional lists, such as those that list open relays, compromised hosts, etc.
In order to use SURBLs you need software that can parse URIs in message bodies, extract their hosts, and check those against a SURBL. Programs such as SpamAssassin 3 and many others now support SURBLs. For a list of some of those applications please see our Links page.