ISC Infrastructure And System Security Practice Question
A security engineer needs to secure SSH access to Linux servers in a cloud VPC. What is the most secure method to replace static SSH keys?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Implement an SSH Certificate Authority (CA) system.
Short-lived, ephemeral SSH certificates generated by an Identity Provider (IdP) eliminate the need for static, long-lived keys.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Implement an SSH Certificate Authority (CA) system.
Why this is correct
SSH CAs allow for identity-based, short-lived certificate issuance.
- ✗
Restrict SSH to a hardened bastion host.
Why it's wrong here
The bastion host itself then becomes a single point of failure.
- ✗
Use a central password manager to rotate keys.
Why it's wrong here
Rotation is better than nothing, but certificates are superior.
- ✗
Require MFA for every single SSH connection.
Why it's wrong here
MFA is good, but it doesn't solve the problem of long-lived key storage.
About these practice questions
This ISC question is part of Courseiva's 208-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed August 2026 · checked against the official (ISC)² exam blueprint
This ISC practice question is part of Courseiva's free (ISC)² certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the ISC exam.