Along with the diffusion of personal computers and the Internet and the development of IT in society, illegal access to computer networks, the public display of child pornography and other indecent images on the Internet, and illegal acquisition of card data, etc. rapidly increased. Therefore, with the aim of prohibiting and punishing these illegal acts, the following legislation and treaties for each high-technology related offense were established and signed respectively.
  For the last few years, the style of illegally accessing acts, which had been characterized by illegally using the passwords of other persons, extended to assault on security holes s, an advanced style of illegal act (Research by the Research and Training Institute of the Ministry of Justice).

Explanation of terms

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High-technology related offenses:
In the Communique of the Denver Summit (which was held in June 1997), "high-technology related offense (high-tech offense)" was used as a term that meant "crimes misusing computers and telecommunications technology", and is a term that has come to be used worldwide.

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Computer offense (in the narrow sense):
There are no specific definitions about this offense, but it is generally used as the term for offenses of which the subjects are computers themselves, such as computer fraud.

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Network offense:
Network offense refers to offenses using a computer network, such as the Internet.

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Unauthorized computer accessing acts:
Regarding computers connected through networks to which access is limited to specific persons, when an unauthorized person uses them by using the passwords of other persons illegally or by giving illegal instructions on computers, to cause malfunction, the acts shall be considered to be unauthorized acts of computer access.

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Assault on security holes:
Assault on security holes refers to the acts of illegally accessing a computer or impeding the operation of a computer by taking advantage of the defects or blind spots of computer programs and systems.