According to a
Washington Post article, Russian spammers took down over 80% of the so-called invincible UltraDNS network on Wednesday (5/17) using a "DNS amplification" attack that UltraDNS was supposedly created specifically to eliminate.
I'm not very surprised, since I've long thought their marketing is incredibly deceptive, but it's a sad state of affairs in general that extortionists can successfully take down the largest providers.
Interestingly, Prolexic, the company that has a near 100% success rate in protecting its customers against even the largest DOS attacks, found many of its customers were affected because Prolexic was relying on UltraDNS. Prolexic founder (and whiz kid) Barrett Lyon indicated to the Post that Prolexic would immediately start working with UltraDNS to fortify their systems to resist future attacks.
All of this came as a result of spammers attacking BlueSecurity, an aggressive anti-spam company that was making considerable inroads in stopping spammers, until it was finally crushed by the DOS attacks this week.
It's really sad that the Internet is still fragile enough that attackers can take basically anyone they wish to offline for hours or days.