ITPEC FE Morning April 2019 Question 36
ITPEC FE Morning April 2019 — Question 36 of 80
DNS Cache Poisoning — identify which user is affected by a poisoned DNS cache entry.
Setup:
- Attacker stored Server X's IP in Company B's DNS cache
- The poisoned entry maps to the FQDN of Company A's web server
- Each company's employees use their own DNS cache server
Who is affected:
- Must use Company B's DNS → must be Company B's employee
- Must request Company A's FQDN → must be accessing Company A's web server
- Answer: Company B employee accessing Company A's web server (c)
Why not others:
- (a) Company A employee → Company A server — uses Company A's DNS (not poisoned)
- (b) Company A employee → Company B server — uses Company A's DNS, different FQDN
- (d) Company B employee → Company B server — uses poisoned DNS, but the poisoned entry is for Company A's FQDN, not Company B's
Key rule: DNS cache poisoning affects users who query the poisoned cache server for the poisoned domain name.
AI-generated — may contain errors
The original exam layout is preserved in the image so diagrams, formulas, tables, and code remain accurate.
This question comes from an official ITPEC past paper. ITPEC Practice is an independent study tool and is not affiliated with ITPEC. See the official FE past-paper collection or Report an issue.