問73
頻出度★★★
IoT デバイスに関わるリスク対策のうち, IoT デバイスが盗まれた場合の耐タンパ性を高めることができるものはどれか。
令和3年度 ITパスポート試験 問73
This question's explanation and your answers so far.
解説
問 73
Incorrectア
Encrypting communication is protection of the communication path that prevents eavesdropping on and tampering with the data flowing between the device and the server; it has nothing to do with resistance to internal analysis of the stolen device itself (tamper resistance).
- イ
正解 Tamper resistance is the property that internal secret information (encryption keys and data) cannot be easily read out even if the device is physically taken apart and analyzed. Option “イ” is a countermeasure that encrypts the data inside the device using a security chip with a built-in encryption key (hardware such as a TPM). The key is hard to extract outside the chip, so even if the device is stolen and its storage is read directly, the encrypted data cannot be decrypted. Because it provides physical protection of the key and resistance to analysis, it reliably enhances tamper resistance when the device is stolen.
Incorrectウ
Applying the latest security patches is a countermeasure against remote attacks that exploit known vulnerabilities and against malware infection. It does not help improve tamper resistance, which prevents the disassembly and analysis of a physically stolen device.
Incorrectエ
Changing the login password from its initial value is a countermeasure that prevents unauthorized login through misuse of the initial password. It has no effect against physical analysis that reads the storage directly, and it does not enhance tamper resistance.
ここがポイント
- Tamper resistance = the property that makes internal secret information hard to extract even when the device is physically disassembled and analyzed; choose the countermeasure designed for theft and physical attacks.
- When you encrypt data with a security chip that has a built-in encryption key (equivalent to a TPM), the key is protected inside the hardware and becomes hard to extract physically, which improves tamper resistance.
用語