High severity malicious activity detected

id: 504257c1-81e2-4609-8d40-b395e62f11c7
name: High severity malicious activity detected
description: |
  Identifies high severity malicious activity in Azure Firewall IDPS logs.
severity: High
status: Available
requiredDataConnectors:
  - connectorId: AzureFirewall
    dataTypes:
      - AZFWIdpsSignature
queryFrequency: 1h
queryPeriod: 24h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - InitialAccess
  - Exfiltration
  - CredentialAccess
  - CommandAndControl
  - Execution
relevantTechniques:
  - T1190
  - T1041
  - T1003
  - T1204
query: |
  let TimeWindow   = 90d;    // How far back to look 
  let HitThreshold = 10;     // Minimum hits to alert per SourceIp + Category
  let MinSeverity  = 1;      // Set Minimum Severity
  let EnableCategoryFilter    = true;   // Filter 1: use CategoriesOfInterest
  let EnableDescriptionFilter = false;  // Filter 2: use DescriptionsOfInterest
  let EnableActionFilter      = false;  // Filter 3: use MatchActions
  let CategoriesOfInterest    = dynamic([
      "Targeted Malicious Activity was Detected",
      "Exploit Kit Activity Detected",
      "Domain Observed Used for C2 Detected",
      "Successful Credential Theft Detected",
      "Malware Command and Control Activity Detected",
      "Executable code was detected",
      "A Network Trojan was detected"
  ]);
  let DescriptionsOfInterest  = dynamic([
      "targeted-activity",
      "exploit-kit",
      "domain-c2",
      "credential-theft",
      "command-and-control",
      "shellcode-detect",
      "trojan-activity"
  ]);
  let MatchActions = dynamic(["Deny", "alert"]);
  AZFWIdpsSignature
  | where TimeGenerated >= ago(TimeWindow)
  | where Severity >= MinSeverity
  // Filter 1: Category filter (optional)
  | where (EnableCategoryFilter == false) or (Category has_any (CategoriesOfInterest))
  // Filter 2: Description filter (optional)
  | where (EnableDescriptionFilter == false) or (Description has_any (DescriptionsOfInterest))
  // Filter 3: Action filter (optional)
  | where (EnableActionFilter == false) or (Action in~ (MatchActions))
  | summarize
      StartTime   = min(TimeGenerated),
      EndTime     = max(TimeGenerated),
      TotalHits   = count(),
      MaxSeverity = max(Severity),
      Actions     = make_set(Action, 5),
      Signatures  = make_set(SignatureId, 20),
      Description = make_set(substring(tostring(Description), 0, 120), 3)
      by SourceIp, ThreatCategory = Category
  | where TotalHits >= HitThreshold
  | project
      StartTime,
      EndTime,
      SourceIp,
      ThreatCategory,
      TotalHits,
      MaxSeverity,
      Actions,
      Signatures,
      Description
  | order by MaxSeverity desc, TotalHits desc
entityMappings:
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: SourceIp
version: 1.0.1
kind: Scheduled