Question 400
An intrusion occurred on an application server and the analyst needs evidence whether it was previously exposed to a known vulnerability. Which evidence source MOST directly answers the investigator’s question?
Explanation
Correct Answer
Historical scan results identify hosts and periods when a known vulnerability was observed. They support exposure reconstruction but do not prove exploitation alone. Read historical scan findings for the application's host identifier, vulnerable service/version, first and last seen dates, and scanner coverage around the incident. This establishes whether the known vulnerability was reported before intrusion; a scan result alone must not be overstated as proof that exploitation actually occurred.
Incorrect Answers
Firewall session logs show network reachability and communications, which can corroborate an attack timeline. They generally do not establish the application version or vulnerability finding that existed on the server before the incident. An egress firewall log can identify network attempts but not whether a specific flaw was known and present on this application server before intrusion.
Packet captures may show an exploit request if complete traffic from the incident was recorded, but the scenario asks whether the asset was *previously exposed*. Historical scan evidence preserves that earlier assessment state more directly than traffic-only observations. A packet trace may capture exploit traffic but does not provide the server’s prior vulnerability inventory and remediation status at the relevant date.
Firewall flow data cannot prove interactive account success. OS login events can identify accounts used around the intrusion, but compromise through an exposed application flaw may not create interactive failed logins. Without vulnerability/version details, those events cannot answer whether a known finding had already been detected on that host.