Japanese nuclear agency warns of cyber attack, turns off email systems

Please fax or phone us with your nuclear questions…

Japanese nuclear agency warns of cyber attack, turns off email systems

Japan’s Nuclear Regulation Authority is asking people to contact it via phone or fax, as it is unable to receive emails from the outside world.

The NRA says on its website that it has temporarily disabled its email systems, suspending its ability to send and receive emails, after suspecting it was under cyber attack.

Japanese NRA announcement

The authority’s email systems were disabled earlier this week and remain down.

According to Japanese media reports, an unknown external party managed to gain unauthorised access to the Nuclear Regulation Authority’s networks. There has been no confirmation that any data was exfiltrated during the security breach, and Deputy Secretary of State Katsuya Okada stressed that information related to nuclear security was held on a separate system that was not connected to the outside world.

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The security breach is being investigated by the authorities in order to properly understand the nature of the attack.

Let the speculation begin on who might be responsible! Nation state or bored teenager? You decide.


Graham Cluley is an award-winning keynote speaker who has given presentations around the world about cybersecurity, hackers, and online privacy. A veteran of the computer security industry since the early 1990s, he wrote the first ever version of Dr Solomon's Anti-Virus Toolkit for Windows, makes regular media appearances, and is the co-host of the popular "The AI Fix" and "Smashing Security" podcasts. Follow him on Bluesky, Mastodon, and Threads, or drop him an email.

One comment on “Japanese nuclear agency warns of cyber attack, turns off email systems”

  1. Mark Jacobs

    With all this Python-fuelled AI about, perhaps SkyNet was knocking on the NRA door! ;-)

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