13.11
IG3

Tune Security Event Alerting Thresholds

Asset Type: Network
Security Function: Detect

Description

Tune security event alerting thresholds monthly, or more frequently.

Implementation Checklist

1
Deploy detection tools or enable detection capabilities
2
Configure alerting thresholds and notification channels
3
Establish monitoring schedule and review process
4
Test detection capabilities with simulated events
5
Document detection procedures and escalation paths

Threats & Vulnerabilities (CIS RAM)

Threat Scenarios

Critical Alert Buried in Excessive False Positives

Confidentiality

A genuine advanced persistent threat alert is lost among thousands of false positive alerts because alerting thresholds have not been tuned, causing analysts to ignore or deprioritize the true positive.

Attacker Evades Detection by Operating Below Static Thresholds

Confidentiality

An attacker deliberately operates just below default detection thresholds that have never been adjusted, successfully exfiltrating data in small increments that never trigger volume-based alerts.

SOC Analyst Burnout Leading to Missed Incidents

Availability

Untuned alerting generates excessive noise that overwhelms security operations staff, causing reduced investigation quality and slower response times when real incidents occur.

Vulnerabilities (When Safeguard Absent)

Static and Unoptimized Alert Thresholds

Without regular threshold tuning, alerting rules remain at default or outdated settings that generate excessive false positives while potentially missing true threats that fall below detection levels.

No Feedback Loop Between Incident Analysis and Detection Rules

Absence of monthly threshold reviews means lessons learned from past incidents and environmental changes are never incorporated into alerting rules, degrading detection effectiveness over time.

Evidence Requirements

Type Evidence Item Collection Frequency
Technical Detection tool deployment evidence (dashboard screenshots, agent status) Captured monthly
Technical Sample alert/detection output demonstrating capability Captured quarterly
Document Governing policy document (current, approved, communicated) Reviewed annually