Question 170
When validating a security detection workflow, the team notes: A daily dashboard shows an external IP responsible for many failed VPN logins and the team wants to identify affected accounts. Which ongoing operational control best reduces the risk of recurrence?
Explanation
Correct Answer
This safeguard directly addresses fortiview failed authentication source ranking: Build combined source- and account-centric authentication detections to avoid missing distributed guessing. The risk being prevented is: A source-ranked failure total does not reveal the identities targeted or whether any session later succeeded. A safeguard aimed at another fault would not control this issue.
Incorrect Answers
An external translated address alone may represent many internal sources and cannot uniquely identify one initiating host. “Retain full session and translation fields needed to attribute shared-address events during investigations” would remedy that alternative situation, but it would not correct the present issue: a source-ranked failure total does not reveal the identities targeted or whether any session later succeeded.
“Overlay change windows on security event trends and retain configuration audit records” is the supported response when a security policy change can create many deny logs that reflect changed enforcement rather than increased attacker attempts. Here the decisive response is “Build combined source- and account-centric authentication detections to avoid missing distributed guessing”, so that different intervention does not meet the stated requirement.
High-frequency or high-entropy DNS patterns can indicate tunneling or automated discovery but can also reflect legitimate software. “Monitor anomalous DNS volume and label findings as hypotheses until corroborated” applies to that other condition. The reported evidence is a daily dashboard shows an external IP responsible for many failed VPN logins and the team wants to identify affected accounts; this alternative would address the wrong dependency.