A security analyst is concerned the number of security incidents being reported has suddenly gone down. Daily business interactions have not changed, and no additional security controls have been…

Changes in DNS configuration would primarily impact network connectivity or name resolution, not directly cause a drop in *reported* security incidents.

Compromised privileged accounts might lead to *more* security incidents or data breaches, not a decrease in reported incidents.

If the number of security incidents has drastically decreased without any change in business operations or security controls, it strongly suggests that the detection system, such as an Intrusion Detection System (IDS), might not be reporting incidents correctly. Reviewing the IDS rule set would confirm if rules have been inadvertently disabled, altered, or are no longer effective, preventing alerts from being generated.

A firewall ACL change might block traffic, potentially reducing *actual* incidents if it blocks malicious traffic, but it wouldn't cause a drop in *reported* incidents unless it also blocks the reporting mechanism itself, which is less likely to be the *first* suspect than the IDS rules responsible for detection.