Killnet claims responsibility for DDoS attacks on Japanese websites

Russia–affiliated hacking gang Killnet claimed responsibility for distributed denial of service (DDoS) attacks against Japanese companies and 20 websites across four government ministries on Tuesday.

The attack began at 4.30 PM Japanese time. Around the time of the attack, Killnet posted a message on its Telegram channel claiming that it had targeted Japan’s online public services and the tax authority’s electronic system. Killnet said it revolted against Tokyo’s “militarism” and was “kicking the samurai.”

At around 6:30 PM on Wednesday, Killnet wrote on Telegram that it had declared war against Japan’s anti-Russian campaign and uploaded a video. Shortly after, at around 7 PM, the group posted again, claiming it would stop Tokyo’s subway network.

Although most services are now restored, a tweet from Japan’s digital agency said its e–Gov administrative portal was experiencing login problems to some services on Wednesday but did not specify the cause.

Japan’s chief cabinet secretary Hirokazu Matsuno said that the Japanese National Center of Incident Readiness and Strategy for Cybersecurity was launching a full investigation into the incident. In particular, the government is investigating whether website problems were caused by a denial-of-service (DDoS) attack.

Notably, Killnet has supported hacktivist activities in support of Vladimir Putin’s government since the start of the conflict in Ukraine, launching DDoS attacks on nations that supported Ukraine and even going so far as to “declare war” on ten nations, including the UK, which was sanctioning Russia.