Cat-hacking Japanese man admits cybercrime guilt

The odd case involved a buried smartphone and clues stashed in a cat's collar

A hacker has confessed in court to hijacking other people's computers to make murder threats in a bizarre case that saw the source code for a virus stashed in the collar of a cat.

Yusuke Katayama, a chubby, bespectacled former IT worker, was accused of sending online messages in 2012 that threatened mass murders at elementary schools and warning of bombs in an airplane and at a shrine.

On Thursday he changed his plea in the case to guilty, according to Japanese press reports. He had been out on bail but was taken back into custody this week.

"It's all true," NHK TV quoted Katayama as telling the Tokyo District Court, a reversal of his not-guilty plea in February.

The online messages were sent via a virus copied to the computers of other people, leading police to make four false arrests.

But what really captured the attention of the Japanese public in the so-called "remote-controlled virus case" was that a message criticizing police -- as well as the source code for the virus -- had been placed in the collar of a stray cat on tiny Enoshima Island, southwest of Tokyo.

Police used surveillance footage of Katayama hanging around the cat as evidence in his arrest in 2013.

After he was released on bail in March, Katayama appeared at a press conference at The Foreign Correspondents' Club of Japan in Tokyo, complaining that he had been "treated 100 percent as a criminal by the media."

But the case took a dramatic turn when email was sent to media outlets last Friday claiming to be from the real culprit in the case. The email was sent while Katayama was in court for a hearing.

Investigators allege that they had followed Katayama and found a smartphone buried along a riverbank in Tokyo that was used to send the email. They also claim Katayama's DNA was on the phone.

Prosecutors took him back into custody on Tuesday after the court revoked his bail.

"In order for the defendant to feel the gravity of what has been done, it's extremely important that the victims in this series of incidents appear in court," defense lawyer Hiroshi Sato told a press conference, adding that Katayama apologized for his actions.

Katayama has apparently made suicidal remarks, and his lawyers may seek a psychiatric evaluation.

Join the CSO newsletter!

Error: Please check your email address.

Tags securitylegalcybercrime

More about Island

Show Comments

Featured Whitepapers

Editor's Recommendations

Solution Centres

Stories by Tim Hornyak

Latest Videos

  • 150x50

    CSO Webinar: The Human Factor - Your people are your biggest security weakness

    ​Speakers: David Lacey, Researcher and former CISO Royal Mail David Turner - Global Risk Management Expert Mark Guntrip - Group Manager, Email Protection, Proofpoint

    Play Video

  • 150x50

    CSO Webinar: Current ransomware defences are failing – but machine learning can drive a more proactive solution

    Speakers • Ty Miller, Director, Threat Intelligence • Mark Gregory, Leader, Network Engineering Research Group, RMIT • Jeff Lanza, Retired FBI Agent (USA) • Andy Solterbeck, VP Asia Pacific, Cylance • David Braue, CSO MC/Moderator What to expect: ​Hear from industry experts on the local and global ransomware threat landscape. Explore a new approach to dealing with ransomware using machine-learning techniques and by thinking about the problem in a fundamentally different way. Apply techniques for gathering insight into ransomware behaviour and find out what elements must go into a truly effective ransomware defence. Get a first-hand look at how ransomware actually works in practice, and how machine-learning techniques can pick up on its activities long before your employees do.

    Play Video

  • 150x50

    CSO Webinar: Get real about metadata to avoid a false sense of security

    Speakers: • Anthony Caruana – CSO MC and moderator • Ian Farquhar, Worldwide Virtual Security Team Lead, Gigamon • John Lindsay, Former CTO, iiNet • Skeeve Stevens, Futurist, Future Sumo • David Vaile - Vice chair of APF, Co-Convenor of the Cyberspace Law And Policy Community, UNSW Law Faculty This webinar covers: - A 101 on metadata - what it is and how to use it - Insight into a typical attack, what happens and what we would find when looking into the metadata - How to collect metadata, use this to detect attacks and get greater insight into how you can use this to protect your organisation - Learn how much raw data and metadata to retain and how long for - Get a reality check on how you're using your metadata and if this is enough to secure your organisation

    Play Video

  • 150x50

    CSO Webinar: How banking trojans work and how you can stop them

    CSO Webinar: How banking trojans work and how you can stop them Featuring: • John Baird, Director of Global Technology Production, Deutsche Bank • Samantha Macleod, GM Cyber Security, ME Bank • Sherrod DeGrippo, Director of Emerging Threats, Proofpoint (USA)

    Play Video

  • 150x50

    IDG Live Webinar:The right collaboration strategy will help your business take flight

    Speakers - Mike Harris, Engineering Services Manager, Jetstar - Christopher Johnson, IT Director APAC, 20th Century Fox - Brent Maxwell, Director of Information Systems, THE ICONIC - IDG MC/Moderator Anthony Caruana

    Play Video

More videos

Blog Posts