Domain registrar said it "came under significant and sustained" DDoS attacks on Sunday that temporarily disabled or slowed many of its hosted websites, CISO Neil Warner said in a statement.

Warner said the company’s security and network teams "invoked counter-measures" to answer the attacks.

"After [four to five] hours of intermittent disruptions of various services this morning, including shared hosting and email, the attack was contained," he said Sunday.

Internet speculation suggested Go Daddy was a victim of a daylight-saving time (DST) issue. But the company denied the speculation, noting that its data center is based in Arizona, unaffected by the clock change.

"With regard to DST, Go Daddy has been engaged in preparation and patching and worked closely with our vendors for some time leading up to the DST change," Warner said.

Go Daddy hosts about one million sites, many of them for small organizations. It has handed out roughly 13 million domain names since its founding in 1997.

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