Preview - TI map IP entity to Cloud App Events

Severity: medium
Time window: 14d
Group by: IPAddress, IndicatorId, TI_ipEntity
Source: github.com/Azure/Azure-Sentinel

Identifies compromises and attacks and detect malicious activities in one's IP entity from TI

MITRE ATT&CK coverage

Tactic	Techniques
Command & Control	`T1071` Application Layer Protocol

Telemetry coverage

Platform	Record / event type
Microsoft Defender for Endpoint	`CloudAppEvents` action `any`: Cloud app activity

Rule body

id: 4e0a6fc8-697e-4455-be47-831b41ea91ac
name: Preview - TI map IP entity to Cloud App Events
description: |
   'Identifies compromises and attacks and detect malicious activities in one's IP entity from TI'
severity: Medium
requiredDataConnectors:
  - connectorId: MicrosoftThreatProtection
    dataTypes:
      - CloudAppEvents
  - connectorId: MicrosoftDefenderThreatIntelligence
    dataTypes:
      - ThreatIntelligenceIndicator
queryFrequency: 1h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - CommandAndControl
relevantTechniques:
  - T1071
query: |
  let dt_lookBack = 1d;
  let ioc_lookBack = 14d; 
  let IP_Indicators = ThreatIntelligenceIndicator
    | where TimeGenerated >= ago(ioc_lookBack)
    | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
    | where Active == true and ExpirationDateTime > now()
    | where isnotempty(NetworkIP)
  or isnotempty(EmailSourceIpAddress)
  or isnotempty(NetworkDestinationIP)
  or isnotempty(NetworkSourceIP)
    | extend TI_ipEntity = iff(isnotempty(NetworkIP), NetworkIP, NetworkDestinationIP)
    | extend TIipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)
    | extend TIipEntity = iff(isempty(TI_ipEntity) and isnotempty(EmailSourceIpAddress), EmailSourceIpAddress, TI_ipEntity);
  IP_Indicators
    | join kind=innerunique (
    CloudAppEvents
      | where isnotempty(IPAddress)
      | where TimeGenerated >= ago(dt_lookBack)
      | extend CloudAppEvents_TimeGenerated = TimeGenerated) on $left.TI_ipEntity == $right.IPAddress
      | where CloudAppEvents_TimeGenerated < ExpirationDateTime
      | summarize CloudAppEventsTimeGenerated = argmax(CloudAppEvents_TimeGenerated, *) by IndicatorId, IPAddress
      | extend
          Description = max_CloudAppEvents_TimeGenerated_Description,
          ActivityGroupNames = max_CloudAppEvents_TimeGenerated_ActivityGroupNames,
          ThreatType = max_CloudAppEvents_TimeGenerated_ThreatType,
          ExpirationDateTime = max_CloudAppEvents_TimeGenerated_ExpirationDateTime,
          ConfidenceScore = max_CloudAppEvents_TimeGenerated_ConfidenceScore,
          TI_ipEntity = max_CloudAppEvents_TimeGenerated_TI_ipEntity,
          NetworkDestinationIP = max_CloudAppEvents_TimeGenerated_NetworkDestinationIP,
          NetworkSourceIP = max_CloudAppEvents_TimeGenerated_NetworkSourceIP,
          EmailSourceIPAddress = max_CloudAppEvents_TimeGenerated_EmailSourceIpAddress
      | project CloudAppEventsTimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, ExpirationDateTime, ConfidenceScore, TI_ipEntity, NetworkDestinationIP, NetworkSourceIP, EmailSourceIPAddress
entityMappings:
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: TI_ipEntity
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: NetworkDestinationIP
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: NetworkSourceIP
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: EmailSourceIPAddress
version: 1.0.3
kind: Scheduled

Stages and Predicates

Parameters

let dt_lookBack = 1d;
let ioc_lookBack = 14d;

let IP_Indicators is inlined into the numbered stages below.

Stages 1 to 6 define let IP_Indicators (the rule's main pipeline source); stages 7 to 11 run on it.

Stage 1: `source`

ThreatIntelligenceIndicator

Stage 2: `where`

| where TimeGenerated >= ago(ioc_lookBack)

Stage 3: `summarize`

| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId

Stage 4: `where`

| where Active == true and ExpirationDateTime > now()

Stage 5: `where`

| where isnotempty(NetworkIP)
or isnotempty(EmailSourceIpAddress)
or isnotempty(NetworkDestinationIP)
or isnotempty(NetworkSourceIP)

Stage 6: `extend` (3 consecutive steps)

| extend TI_ipEntity = iff(isnotempty(NetworkIP), NetworkIP, NetworkDestinationIP)
| extend TIipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)
| extend TIipEntity = iff(isempty(TI_ipEntity) and isnotempty(EmailSourceIpAddress), EmailSourceIpAddress, TI_ipEntity)

TI_ipEntity =

ifisnotempty(NetworkIP)NetworkIP

elseNetworkDestinationIP

Stage 7: `join`

IP_Indicators
| join kind=innerunique (
  CloudAppEvents
    | where isnotempty(IPAddress)
    | where TimeGenerated >= ago(dt_lookBack)
    | extend CloudAppEvents_TimeGenerated = TimeGenerated) on $left.TI_ipEntity == $right.IPAddress

Stage 8: `where`

| where CloudAppEvents_TimeGenerated < ExpirationDateTime

Stage 9: `summarize`

| summarize CloudAppEventsTimeGenerated = argmax(CloudAppEvents_TimeGenerated, *) by IndicatorId, IPAddress

Stage 10: `extend`

| extend
        Description = max_CloudAppEvents_TimeGenerated_Description,
        ActivityGroupNames = max_CloudAppEvents_TimeGenerated_ActivityGroupNames,
        ThreatType = max_CloudAppEvents_TimeGenerated_ThreatType,
        ExpirationDateTime = max_CloudAppEvents_TimeGenerated_ExpirationDateTime,
        ConfidenceScore = max_CloudAppEvents_TimeGenerated_ConfidenceScore,
        TI_ipEntity = max_CloudAppEvents_TimeGenerated_TI_ipEntity,
        NetworkDestinationIP = max_CloudAppEvents_TimeGenerated_NetworkDestinationIP,
        NetworkSourceIP = max_CloudAppEvents_TimeGenerated_NetworkSourceIP,
        EmailSourceIPAddress = max_CloudAppEvents_TimeGenerated_EmailSourceIpAddress

Stage 11: `project`

| project CloudAppEventsTimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, ExpirationDateTime, ConfidenceScore, TI_ipEntity, NetworkDestinationIP, NetworkSourceIP, EmailSourceIPAddress

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`Active`	eq	`true`	`field:"Active" kind:eq value:"true"`
`CloudAppEvents_TimeGenerated`	cross_field_compare	`ExpirationDateTime` transforms: `op:lt`	`field:"CloudAppEvents_TimeGenerated" kind:cross_field_compare value:"ExpirationDateTime"`
`EmailSourceIpAddress`	is_not_null	(no value, null check)	`field:"EmailSourceIpAddress" kind:is_not_null`
`IPAddress`	is_not_null	(no value, null check)	`field:"IPAddress" kind:is_not_null`
`NetworkDestinationIP`	is_not_null	(no value, null check)	`field:"NetworkDestinationIP" kind:is_not_null`
`NetworkIP`	is_not_null	(no value, null check)	`field:"NetworkIP" kind:is_not_null`
`NetworkSourceIP`	is_not_null	(no value, null check)	`field:"NetworkSourceIP" kind:is_not_null`

Output fields

These fields are emitted when the rule matches.

Field	Source
`ActivityGroupNames`	`project`
`CloudAppEventsTimeGenerated`	`project`
`ConfidenceScore`	`project`
`Description`	`project`
`EmailSourceIPAddress`	`project`
`ExpirationDateTime`	`project`
`IndicatorId`	`project`
`NetworkDestinationIP`	`project`
`NetworkSourceIP`	`project`
`TI_ipEntity`	`project`
`ThreatType`	`project`

Preview - TI map IP entity to Cloud App Events

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Parameters

Stage 1: source

Stage 2: where

Stage 3: summarize

Stage 4: where

Stage 5: where

Stage 6: extend (3 consecutive steps)

Stage 7: join

Stage 8: where

Stage 9: summarize

Stage 10: extend

Stage 11: project