Certified Ethical Hacker (CEH v12) — Question 34

Dorian is sending a digitally signed email to Poly. With which key is Dorian signing this message and how is Poly validating it?

Answer options

• A. Dorian is signing the message with his public key, and Poly will verify that the message came from Dorian by using Dorian’s private key.
• B. Dorian is signing the message with Poly’s private key, and Poly will verify that the message came from Dorian by using Dorian’s public key.
• C. Dorian is signing the message with his private key, and Poly will verify that the message came from Dorian by using Dorian’s public key.
• D. Dorian is signing the message with Poly’s public key, and Poly will verify that the message came from Dorian by using Dorian’s public key.

Correct answer: C

Explanation

The correct answer is C because Dorian uses his private key to sign the message, which allows Poly to verify the signature using Dorian's public key. Options A and D are incorrect as they incorrectly attribute the signing and verification keys. Option B is also wrong because it mistakenly suggests that Dorian uses Poly's private key, which is not how digital signatures work.