A Tokyo district court has jailed a 28 year-old Japanese man after he was found guilty of creating and distributing the ika tako computer virus and destroying data in the infected computers.
The conviction, the first in Japan to see property destruction charges levelled against a malware writer, will see Masato Nakatsuji of Izumisano, Osaka prefecture, sentenced to two years and six months behind bars, according to a Daily Yomiuri report.
V3 reported back in August 2010 of Nakatsuji's arrest on suspicion of writing the ika tako, or 'squid octopus', virus which was distributed on the Winny file-sharing site in May disguised as a file for anime songs.
The virus gets its name by deleting the victim's computer files and replacing them with manga-style images of octopuses and squid.
Nakatsuji's defence lawyers had claimed that the virus only made the victims' hard disks temporarily unusable, but Judge Masaru Okabe decided that some of the data on them had been completely lost, according to the Yomiuri.
"It was an ingenious, planned crime to spread a computer virus over a long period of time," he is reported as saying.
"The defendant committed the crime while he was on probation for a similar charge. I have no choice but to give him a sentence without suspension."
In 2008, Nakatsuji became the first malware writer arrested in Japan after spreading a virus attached to anime images. With no computer crime law at the time, he was convicted under the country's copyright law.
"Once again, it's clear that some people have not got the message that malware is not a fun game, but can have serious consequences," said Sophos senior technology consultant Graham Cluley in a blog post.
"Maybe Masato Nakatsuji's spell in prison will give him plenty of time to reflect on that."
Last month, Japan finally enacted a cyber crime bill meaning that those found guilty of creating or distributing malware could get a maximum of three years in prison or ¥500,000 (£3,855) in fines, while the acquisition or storage of a virus is punishable by up to two years in prison or ¥300,000 (£2,315) in fines.
The new law brings Japan closer to joining the international Convention on Cybercrime.
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