The international non-profit organization, which tracks spam-related activity and provides a blacklist of IP blocks used by known spamming outfits that is used by the majority of anti-spam filters out there, has apparently been targeted by Dutch hosting provider Cyberbunker and/or its spamming customers.
While the initial attacks knocked Spamhaus' website and blacklists offline, the organization quickly reacted by enlisting CloudFlare to help them bear the brunt of it. And not a moment to soon, as it turned out, as the attackers changed tack and used the DNS reflection technique to amplify the attack (check out CloudFlare CEO's extremely thorough blog post for details about it).
The attack - the biggest of this kind in the history of the Internet - has reportedly even affected the Internet as a whole and users of certain popular services - unrelated to Spamhaus or CloudFlare - have experienced temporary service deterioration.
According to the BBC, cyber divisions of five different national police forces around the world are investigating the attacks.