212-89 Network Incidents Practice Question
Which technique should an incident responder use to prevent an infected host from spreading ransomware via SMB to other segments in the network?
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 ACLs to block TCP 445 between segments
Blocking TCP 445 (SMB) at the boundary between network segments is the most effective way to stop worm-like lateral movement.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Disable DNS resolution on the host
Why it's wrong here
This will break host functionality but not stop SMB propagation.
- ✗
Enable DHCP snooping
Why it's wrong here
DHCP snooping protects against rogue DHCP servers, not SMB propagation.
- ✗
Flush the ARP cache
Why it's wrong here
Flushing ARP cache is a temporary mitigation that will not stop persistent SMB attempts.
- ✓
Implement ACLs to block TCP 445 between segments
Why this is correct
Blocking the SMB port prevents the lateral propagation of ransomware.
About these practice questions
Courseiva writes every 212-89 question from scratch — 206 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 EC-Council exam blueprint
This 212-89 practice question is part of Courseiva's free EC-Council 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 212-89 exam.