問98
頻出度★★★
ランサムウェアに関する記述として, 最も適切なものはどれか。
令和6年度 ITパスポート試験 問98
テクノロジ系セキュリティ › 情報セキュリティ
This question's explanation and your answers so far.
解説
問 98
Incorrectア
Secretly planting an intrusion path for unauthorized login from the outside describes a “backdoor”. Its purpose is to set up a persistent unauthorized entry point; it does not involve encrypting files or demanding money, so it is not ransomware.
- イ
正解 Ransomware is malware whose name comes from “ransom” plus “software”. It encrypts the files on an infected PC without permission so they can no longer be used, and demands money (a ransom) in exchange for things such as handing over the key needed to restore (decrypt) them. Choice イ directly describes this core behavior of encrypting files and demanding a ransom, so it is the most appropriate.
Incorrectウ
Hijacking a web browser and breaking into communications such as online banking to make unauthorized transfers describes an “MITB (Man-in-the-Browser) attack”. Its aim is to steal funds by intervening in the communication, which differs from ransomware’s encryption and ransom demand.
Incorrectエ
Spreading infection by itself over a network and proliferating describes a “worm”. Its defining trait is self-replication and propagation, which is a different thing from ransomware that encrypts files and demands money.
ここがポイント
- Ransomware = malware that encrypts files to make them unusable and demands a ransom in exchange for decryption (the name comes from “ransom”).
- Distinguishing confusing malware: backdoor (setting up an intrusion path) / MITB (unauthorized transfers via browser hijacking) / worm (self-replicating and spreading).
用語