How does public key infrastructure (PKI) help to verify that a digitally signed document is not a forgery?

The correct answer is A. By decrypting the signature with the signer's public key. In PKI, when a document is digitally signed: The signer uses their private key to create the signature. The recipient uses the signer's public key to decrypt and verify the signature. If the decrypted hash matches the document's computed hash, the document is authentic and Option

Submitted by andreas_gr· Apr 18, 2026Protection of Information Assets

Question

Options

ABy decrypting the signature with the signer's public key
BBy verifying the signature with the signer's private key
CBy checking the signature against the receiver's public key
DBy checking the signed document's audit history

How the community answered

(55 responses)

A
89% (49)
B
5% (3)
C
2% (1)
D
4% (2)

Explanation

In PKI, when a document is digitally signed: The signer uses their private key to create the signature. The recipient uses the signer's public key to decrypt and verify the signature. If the decrypted hash matches the document's computed hash, the document is authentic and Option A: Correct - verification is done with the public key. Option B: Incorrect - the private key is only used to sign, not verify. Option C: Wrong - the receiver's public key is irrelevant. Option D: Not applicable - audit history is not part of PKI validation.

Topics

#PKI#Digital Signatures#Cryptography#Authentication

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