This question's explanation and your answers so far.
不適切な行為 a～d のうち, 不正アクセス禁止法において規制される行為だけを全て挙げたものはどれか。 a Web サイトにアクセスしただけで直ちに有料会員として登録する仕組みを作り, 利用者に料金を請求する。 b コンピュータのプログラムで様々な組合せのメールアドレスを生成し, それを宛先として商品の広告を発信する。 c 他人のクレジットカードから記録情報を読み取って偽造カードを作成し, 不正に商品を購入する。 d 他人の利用者 ID とパスワードを本人に無断で用いてインターネットショッピングのサイトにログインし, その人の購買履歴を閲覧する。
This option lists all of a, b, c, and d, but only d falls under the Unauthorized Access Prohibition Act. Act a is one-click fraud (crimes such as fraud), b is spam email covered by laws such as the Specified Commercial Email Act, and c is the counterfeiting and illegal use of a credit card (unauthorized creation of electromagnetic records of payment cards, fraud, and the like); none of these are regulated by the Unauthorized Access Prohibition Act.
This option lists a, c, and d, but both a (a one-click fraud mechanism aimed at billing) and c (making a counterfeit card from another person's credit card information and using it for illegal purchases) fall not under the Unauthorized Access Prohibition Act but under other laws such as those on fraud and counterfeiting. Therefore it is wrong because it includes acts other than d.
This option lists c and d, but c is the act of reading the recorded information from a credit card to make a counterfeit card and make illegal purchases, not an impersonated login to an access-controlled device. It falls under acts such as unauthorized creation and use of electromagnetic records of payment cards and fraud, and is not regulated by the Unauthorized Access Prohibition Act, so it is wrong because it includes c.
正解 The Unauthorized Access Prohibition Act regulates acts such as logging in by entering another person's identification codes (user ID and password) without permission into an access-controlled device — that is, impersonation — and unauthorized intrusion that exploits a security hole. Act d is logging in to a shopping site using another person's user ID and password without their permission and viewing that person's purchase history, which is exactly this kind of unauthorized access through impersonation. Therefore only d is regulated, so the correct answer is エ.