Detection rules › Kusto

CMMC 2.0 Level 2 (Advanced) Readiness Posture

Status
available
Severity
medium
Time window
7d
Group by
AssessedResourceId, Level, RecommendationName
Source
github.com/Azure/Azure-Sentinel

'CMMC 2.0 Level 2 (Advanced) assessments have deviated from configured threshold baselines. This alert is triggered when CMMC2.0 policy compliance is assessed below 70% compliance in 7 days.'

MITRE ATT&CK coverage

TacticTechniques
DiscoveryT1082 System Information Discovery

Rule body kusto

id: 7bfe573b-3069-4e81-98fe-9a4cffbcbc24
name: CMMC 2.0 Level 2 (Advanced) Readiness Posture
description: |
  'CMMC 2.0 Level 2 (Advanced) assessments have deviated from configured threshold baselines. This alert is triggered when CMMC2.0 policy compliance is assessed below 70% compliance in 7 days.'
severity: Medium
status: Available
requiredDataConnectors: []
queryFrequency: 7d
queryPeriod: 7d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Discovery
relevantTechniques:
  - T1082
query: |
  SecurityRegulatoryCompliance
  | where ComplianceStandard == "NIST-SP-800-171-R2"
  | extend Level=iff(ComplianceControl in ("3.1.1","3.1.2","3.1.20","3.1.22","3.4.1","3.5.2","3.5.2","3.8.3","3.13.1","3.13.5","3.14.1","3.14.2","3.14.4","3.14.5"), "Level 1: Foundational","Level 2: Advanced")
  | where Level == "Level 2: Advanced"
  | summarize arg_max(TimeGenerated, *) by RecommendationName, AssessedResourceId, Level
  |summarize Failed=countif(State=="Failed"),Passed=countif(State=="Passed"),Total=countif(State=="Passed" or State == "Failed") by Level
  |extend PassedControlsPercentage = (Passed/todouble(Total))*100
  | where PassedControlsPercentage < 70 
  //Adjust Either Passed Thresholds within Organizational Needs
  | extend RemediationLink = strcat('https://portal.azure.com/#blade/Microsoft_Azure_Security/SecurityMenuBlade/22')
  | project Level, Total, PassedControlsPercentage, Passed, Failed, RemediationLink, LastObserved=now()
  | extend URLCustomEntity = RemediationLink
entityMappings:
  - entityType: URL
    fieldMappings:
      - identifier: Url
        columnName: URLCustomEntity
version: 1.0.0
kind: Scheduled

Stages and Predicates

Stage 1: source

SecurityRegulatoryCompliance

Stage 2: where

| where ComplianceStandard == "NIST-SP-800-171-R2"

Stage 3: extend

| extend Level=iff(ComplianceControl in ("3.1.1","3.1.2","3.1.20","3.1.22","3.4.1","3.5.2","3.5.2","3.8.3","3.13.1","3.13.5","3.14.1","3.14.2","3.14.4","3.14.5"), "Level 1: Foundational","Level 2: Advanced")
Level =
ifComplianceControl in ("3.1.1", "3.1.2", "3.1.20", "3.1.22", "3.4.1", "3.5.2", "3.5.2", "3.8.3", "3.13.1", "3.13.5", "3.14.1", "3.14.2", "3.14.4", "3.14.5")"Level 1: Foundational"
else"Level 2: Advanced"

Stage 4: where

| where Level == "Level 2: Advanced"

Stage 5: summarize

| summarize arg_max(TimeGenerated, *) by RecommendationName, AssessedResourceId, Level

Stage 6: summarize

| summarize Failed=countif(State=="Failed"),Passed=countif(State=="Passed"),Total=countif(State=="Passed" or State == "Failed") by Level

Stage 7: extend

| extend PassedControlsPercentage = (Passed/todouble(Total))*100

Stage 8: where

| where PassedControlsPercentage < 70

Stage 9: extend

| extend RemediationLink = strcat('https://portal.azure.com/#blade/Microsoft_Azure_Security/SecurityMenuBlade/22')

Stage 10: project

| project Level, Total, PassedControlsPercentage, Passed, Failed, RemediationLink, LastObserved=now()

Stage 11: extend

| extend URLCustomEntity = RemediationLink

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
ComplianceStandardeq
  • NIST-SP-800-171-R2 transforms: cased
Leveleq
  • Level 2: Advanced transforms: cased
PassedControlsPercentagelt
  • 70 transforms: cased

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

FieldSource
Failedproject
LastObservedproject
Levelproject
Passedproject
PassedControlsPercentageproject
RemediationLinkproject
Totalproject
URLCustomEntityextend