Recent Ukraine outage caused by modest cyberattack, data shows

(Reuters) — The blast of rogue traffic that briefly overwhelmed Ukrainian servers earlier this week was modest compared with digital onslaughts recorded elsewhere, U.S. company Netscout Systems Inc. said Thursday.

The distributed denial of service — often abbreviated DDoS — hit Ukraine's defense ministry website and several banks on Tuesday, briefly knocking them offline and interrupting services. 

Kyiv blamed Moscow for the digital disruption amid heightened tensions since Russia began massing more than 100,000 troops near the border, raising fears it is planning to attack Ukraine. The Kremlin denied involvement in the denial of service and has repeatedly denied it plans to invade Ukraine. 

Ukrainian officials described the outages as the result of "the largest DDoS ​attack in the history of Ukraine," but Netscout said that the digital flood was pretty standard.

"It's possible that it was the largest they'd seen against targets," said Richard Hummel, who heads the threat intelligence team at Netscout's ASERT unit.

"It is definitely not the largest we've seen."

Mr. Hummel cautioned that Netscout's information was drawn from "observations from the outside looking in," but his assessment echoed what San Francisco-based Cloudflare, a prominent provider of denial of service protection, told Reuters on Wednesday.

In an email, the company said it had seen no evidence of “large DDoS activity” in Ukraine against its data centers or customers there.