Hackers behind Kadokawa Cyberattack Claim Further Info Leak

Yomiuri Shimbun file photo

Tokyo, July 2 (Jiji Press) — Hackers who stole data from Japanese publisher Kadokawa Corp. through a cyberattack have claimed that they leaked additional stolen information, the embattled company said Tuesday.

Kadokawa said that it is investigating the authenticity of the claim, and called on people not to share any such data on social media as it could have serious repercussions.

A hacker group calling itself BlackSuit published a statement on the dark web, a highly anonymous part of the internet, claiming responsibility for the data breach, which caused suspensions of Kadokawa services including the Niconico video-sharing platform. It threatened to publish the data Monday unless a ransom was paid.

The group is believed to have stolen 1.5 terabytes of data, including information on contracts with business partners and user information.

The Niconico platform and other services became unavailable from June 8 following a cyberattack using a ransomware virus that encrypts data and seeks a ransom in exchange for a decryption key.

Kadokawa, which is using a temporary system, said Friday that it has confirmed leaks of some of the data, including personal information of all employees at unit Dwango Co., which operates the Niconico platform.