A software vendor publishes a signed release announcement. To verify the authenticity of the announcement, a user imports the vendor's public key and runs `gpg --verify announcement.txt.sig announcement.txt`. The command succeeds. What does this verify?

The announcement is encrypted and can only be read by the vendor.

The announcement was created by the vendor's public key.

The vendor's public key is trusted by a certificate authority.

The announcement was signed by the vendor's private key and has not been modified since signing.

A company's internal CA is compromised. The administrator needs to ensure that certificates issued by the compromised CA are no longer trusted. Which action should the administrator take?

Publish a Certificate Revocation List (CRL) and distribute it to clients.

Renew the CA's certificate with a longer validity period.

Reissue all certificates with the same key pair.

Delete the CA's private key from the server.

How does asymmetric encryption differ from symmetric encryption in terms of key usage?

Asymmetric uses a public/private key pair; symmetric uses a single shared key

Asymmetric is used only for hashing; symmetric is used for encryption

Asymmetric requires a passphrase; symmetric does not

Asymmetric uses a single key; symmetric uses a key pair

Which component is a core part of a Public Key Infrastructure (PKI)?

Intrusion Detection System (IDS)

A systems administrator needs to encrypt a sensitive configuration file before transferring it to a backup server. The backup server only supports standard Linux file encryption tools and the administrator must be able to decrypt the file later using a passphrase. Which command should the administrator use?

openssl enc -aes-256-cbc -salt -in config.conf -out config.enc

gpg --encrypt --recipient backup@example.com config.conf

openssl dgst -sha256 -sign private.key -out config.sig config.conf

sha256sum config.conf > config.sha256

CompTIALinux+

Domain 3Objective 5

Cryptography XK0-006 Practice Questions (Page 1)

Part of the Security domain, which accounts for 18% of the XK0-006 exam. CompTIA does not publish an official question count, but from its 90-minute exam (~35–60 total, ~6–11 in this domain), expect 1–2 from this objective — we provide 35 practice questions to prepare you well beyond it. (estimate)

35questions here

7free pages

9concepts

18%of the exam

Questions 1–5

1application · medium
A software vendor publishes a signed release announcement. To verify the authenticity of the announcement, a user imports the vendor's public key and runs `gpg --verify announcement.txt.sig announcement.txt`. The command succeeds. What does this verify?
Select an answer first
2expert · hard
A company's internal CA is compromised. The administrator needs to ensure that certificates issued by the compromised CA are no longer trusted. Which action should the administrator take?
Select an answer first
3foundation · easy
How does asymmetric encryption differ from symmetric encryption in terms of key usage?
Select an answer first
4foundation · easy
Which component is a core part of a Public Key Infrastructure (PKI)?
Select an answer first
5application · medium
A systems administrator needs to encrypt a sensitive configuration file before transferring it to a backup server. The backup server only supports standard Linux file encryption tools and the administrator must be able to decrypt the file later using a passphrase. Which command should the administrator use?
Select an answer first

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