A cybersecurity analyst is doing triage in a SIEM and notices that the time stamps between the firewall and the host under investigation are off by…

A time discrepancy of 43 minutes is arbitrary and does not correspond to a standard time zone offset, which would typically be in full or half-hour increments. This strongly suggests that one of the devices is experiencing clock drift due to a lack of time synchronization. The Network Time Protocol (NTP) is the standard used to synchronize clocks across a network. In a typical corporate environment, critical infrastructure like a firewall is properly configured with NTP. Therefore, the most probable cause is that the host's clock is not synchronized with an NTP server, causing it to drift over time and creating a time gap when its logs are correlated with other sources in the SIEM.

B. This suggests human error, but the question asks for the most likely scenario occurring with the time stamps, implying a technical cause for the discrepancy itself.

C. A difference between UTC and a local time zone would result in an offset of one or more full hours (or half-hours), not an arbitrary value like 43 minutes.

D. A host being offline would mean it stops sending logs, but it does not explain why the timestamps in the logs it already sent are out of sync.

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1. National Institute of Standards and Technology (NIST). (2006). Guide to Computer Security Log Management (Special Publication 800-92).

Section 4.3.1

Time Stamps

Page 4-4: "If the clocks on hosts are not synchronized

it is impossible to have a consistent time reference... The Network Time Protocol (NTP) is typically used to perform time synchronization. Without proper time synchronization

it is impossible to determine the order in which events occurred from their log entries." This directly supports that a lack of synchronization (via NTP) causes time reference issues

which is the root of the problem in the scenario.

2. Zeltser

L. (2012). SANS Institute InfoSec Reading Room: Critical Log Review Checklist for Security Incidents.

Section: Time Synchronization

Page 3: "Confirm that all systems involved in the incident had their time synchronized to a common time source. If time was not synchronized

determine the time offset for each system." This highlights time synchronization as a critical first step in incident analysis and triage

reinforcing that its absence is a common and significant problem.

3. CompTIA. (2022). CompTIA Cybersecurity Analyst (CySA+) CS0-003 Exam Objectives.

Section 2.3

Page 10: This objective requires the candidate to "analyze data as part of security monitoring activities

" specifically mentioning "Log - Timestamps." The scenario directly tests the analyst's ability to interpret and troubleshoot issues with log timestamps

a core competency for the exam. The discrepancy points to a failure in the underlying mechanism (NTP) responsible for maintaining accurate timestamps.