Detection rules › Kusto

Filewall - Blocked files

Status
available
Severity
high
Time window
5m
Source
github.com/Azure/Azure-Sentinel

Identifies files blocked by Filewall for Microsoft 365 (SharePoint/OneDrive/Teams).

MITRE ATT&CK coverage

Rule body kusto

id: 86e7f6fd-5c29-4a3a-bced-3eca3fb0c621
name: Filewall - Blocked files
description: Identifies files blocked by Filewall for Microsoft 365 (SharePoint/OneDrive/Teams).
severity: High
status: Available
kind: Scheduled
query: |
  FilewallM365FileEvent()
  | where EventVendor == 'ODI-X' and EventProduct == 'Filewall for Microsoft 365'
  | where EventType == 'FileBlocked'
queryFrequency: 5m
queryPeriod: 5m
triggerOperator: gt
triggerThreshold: 0
relevantTechniques:
- T1048
tactics:
- Exfiltration
eventGroupingSettings:
  aggregationKind: AlertPerResult
incidentConfiguration:
  createIncident: true
  groupingConfiguration:
    matchingMethod: AllEntities
    reopenClosedIncident: false
    enabled: false
    lookbackDuration: PT1H
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: FullName
    columnName: ActorUsername
- entityType: File
  fieldMappings:
  - identifier: Name
    columnName: TargetFileName
  - identifier: Directory
    columnName: TargetFilePath
requiredDataConnectors:
- dataTypes:
  - FilewallFile_CL
  connectorId: FilewallM365
version: 1.0.0

Stages and Predicates

Stage 1: source

FilewallM365FileEvent()

Stage 2: where

| where EventVendor == 'ODI-X' and EventProduct == 'Filewall for Microsoft 365'

Stage 3: where

| where EventType == 'FileBlocked'

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
EventProducteq
  • Filewall for Microsoft 365 transforms: cased
EventTypeeq
  • FileBlocked transforms: cased
EventVendoreq
  • ODI-X transforms: cased