ISC Infrastructure And System Security Practice Question
Which THREE of the following are indicators of a potential system compromise?
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
✓
Unexpected outbound network traffic.
Unusual login times, unauthorized file modification, and unexpected network traffic are common indicators of compromise (IoC).
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Normal user logons.
Why it's wrong here
Normal behavior is not an indicator.
- ✓
Unexpected outbound network traffic.
Why this is correct
Common sign of C2 activity.
- ✗
Scheduled system backups.
Why it's wrong here
This is normal system activity.
- ✓
Unusual login times or locations.
Why this is correct
Common sign of account compromise.
- ✓
Unauthorized modification of system files.
Why this is correct
Sign of persistence or rootkit installation.
About these practice questions
Courseiva writes every ISC question from scratch — 208 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or 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.