One in every 24 Googlebots is a imitation spam-flinging denial of service villain that masquerades as Mountain View to sneak past web perimeter defences, according to security chaps at Incapsula. Villains spawn the "evil twins" to hack and crack legitimate websites and form what amounted to the third most-popular type of DDoS attack to scourge the internet.
Incapsula detected 50 million unwanted visits by the fake bots which made up four percent of all legitimate Googlebot HTTPS user-agents.

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