Composite Blocking List (CBL)
cbl.abuseat.org
Operated by abuseat.org
Avg removal time
Immediate upon successful self-service removal
This blacklist severely impacts email deliverability with major ISPs and enterprise mail servers.
About Composite Blocking List (CBL)
The CBL (now part of the Spamhaus XBL) lists IPs that have exhibited characteristics of spam-sending malware or are known open proxies and open relays. It is one of the most technically rigorous blocklists, focusing on automated spam sources.
Why am I listed?
IPs are listed when they connect directly to CBL spam traps in a way characteristic of known spam malware, or when they are detected as open HTTP/SOCKS proxies or open relays being exploited by spammers.
How to get delisted
Follow these steps in order to request removal from Composite Blocking List (CBL).
- 1
Visit abuseat.org and enter your IP to check the listing.
- 2
The site provides specific information about why your IP was listed.
- 3
Scan the host at the IP for malware — common culprits include botnet infections and proxy software.
- 4
Remove all malware and secure any open proxies or relays.
- 5
Use the self-service removal form on abuseat.org after cleaning the host.
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