The Spamhaus Project


Update for Composite Blocklist (CBL) Users

by The Spamhaus TeamDecember 18, 20202 minutes reading time

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As of the first week of 2021, the Composite Blocklist (CBL) is being retired. This data, however, is included in the eXploits Blocklist (XBL). We advise any users currently accessing the CBL through to reconfigure and query

Will access be stopped for

No. Access will remain open for some time, and data will continue to be served for However, please remember that this is becoming a legacy service, so we do advise querying

Are the usage terms and conditions changing?

Yes. As of January 4th, 2021, any users of the CBL will be subject to the same terms and conditions as the rest of Spamhaus’ datasets.

As a result, the same DNS Access Controls (ACLs), including query limits, that apply to Spamhaus’ data will also apply to users of the CBL. If you are a small scale user, we recommend using the free Data Query Service, managed by Spamhaus Technology.

Why is this happening?

Operational since 2003, the CBL went on to become a component of the XBL, which was launched in 2004. Meanwhile, the CBL became its own entity operating as a subdivision of Spamhaus.

Given Spamhaus’ focus on improving integration across our datasets and increasing the number of access methods, the time has come for all CBL data to be served from the XBL.

Where do I go to check CBL listings and removals?

Spamhaus will solely manage CBL listings, inquiries, and removals through our lookup pages. A redirection will be in place from

Is the data going to change?

CBL and XBL data have mirrored one another for years. Initially, users of the public mirrors may notice an increase in detection rates. This is because the new infrastructure is almost instantaneous in adding new IPs.

Conversely, users consuming the rsync version of the XBL will notice a reduction in the zone size: this comes as a result of more aggressive data expiration in the new setup.