TI Map Domain Entity to DeviceNetworkEvents

Severity: medium
Time window: 14d
Group by: Domain, DomainName, Id, IndicatorId, ObservableValue
Source: github.com/Azure/Azure-Sentinel

This query identifies any Domain indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in DeviceNetworkEvents.

MITRE ATT&CK coverage

Tactic	Techniques
Command & Control	`T1071` Application Layer Protocol

Telemetry coverage

Platform	Record / event type
Microsoft Defender for Endpoint	`DeviceNetworkEvents` action `any`: Network activity

Rule body

id: 1546f3b3-de8a-4e62-bfea-815422154981
name: TI Map Domain Entity to DeviceNetworkEvents
description: |
  'This query identifies any Domain indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in DeviceNetworkEvents.'
severity: Medium
requiredDataConnectors:
  - connectorId: MicrosoftThreatProtection
    dataTypes:
      - DeviceNetworkEvents
  - connectorId: ThreatIntelligence
    dataTypes:
      - ThreatIntelIndicators
  - connectorId: ThreatIntelligenceTaxii
    dataTypes:
      - ThreatIntelIndicators
  - connectorId: MicrosoftDefenderThreatIntelligence
    dataTypes:
      - ThreatIntelIndicators
queryFrequency: 1h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - CommandAndControl
relevantTechniques:
  - T1071
query: |
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let DeviceNetworkEvents_ = DeviceNetworkEvents
    | where isnotempty(RemoteUrl)
    | where TimeGenerated >= ago(dt_lookBack)
    | where ActionType !has "ConnectionFailed"
    | extend Domain = tostring(parse_url(tolower(RemoteUrl)).Host)
    | where isnotempty(Domain)
    | project-rename DeviceNetworkEvents_TimeGenerated = TimeGenerated;
  let DeviceNetworkEventDomains = DeviceNetworkEvents_
    | distinct Domain
    | summarize make_list(Domain);
  ThreatIntelIndicators
  | extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
  | where IndicatorType == "domain-name"
  | extend DomainName = tolower(ObservableValue)
  | where TimeGenerated >= ago(ioc_lookBack)
  | extend IndicatorId = tostring(split(Id, "--")[2])
  | where DomainName in (DeviceNetworkEventDomains)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
  | where IsActive and (ValidUntil > now() or isempty(ValidUntil))
  | extend Description = tostring(parse_json(Data).description)
  | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
  | where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
  | project-reorder *, IsActive, Tags, TrafficLightProtocolLevel, DomainName, Type
  | join kind=innerunique (DeviceNetworkEvents_) on $left.DomainName == $right.Domain
  | where DeviceNetworkEvents_TimeGenerated < ValidUntil
  | summarize DeviceNetworkEvents_TimeGenerated = arg_max(DeviceNetworkEvents_TimeGenerated, *) by IndicatorId
  | project DeviceNetworkEvents_TimeGenerated, IndicatorId, Url = RemoteUrl, Confidence, Description, Tags, TrafficLightProtocolLevel, ActionType, DeviceId, DeviceName, InitiatingProcessAccountUpn, InitiatingProcessCommandLine, RemoteIP, RemotePort
  | extend Name = tostring(split(InitiatingProcessAccountUpn, '@', 0)[0]), UPNSuffix = tostring(split(InitiatingProcessAccountUpn, '@', 1)[0])
  | extend timestamp = DeviceNetworkEvents_TimeGenerated, UserPrincipalName = InitiatingProcessAccountUpn
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: Name
      - identifier: UPNSuffix
        columnName: UPNSuffix
  - entityType: Host
    fieldMappings:
      - identifier: FullName
        columnName: DeviceName
  - entityType: URL
    fieldMappings:
      - identifier: Url
        columnName: Url
  - entityType: Process
    fieldMappings:
      - identifier: CommandLine
        columnName: InitiatingProcessCommandLine
version: 1.0.4
kind: Scheduled

Stages and Predicates

Parameters

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

Let binding: `DeviceNetworkEvents_` used in Stages 1, 16

let DeviceNetworkEvents_ = DeviceNetworkEvents
  | where isnotempty(RemoteUrl)
  | where TimeGenerated >= ago(dt_lookBack)
  | where ActionType !has "ConnectionFailed"
  | extend Domain = tostring(parse_url(tolower(RemoteUrl)).Host)
  | where isnotempty(Domain)
  | project-rename DeviceNetworkEvents_TimeGenerated = TimeGenerated;

Let binding: `DeviceNetworkEventDomains` used in Stages 2, 9

let DeviceNetworkEventDomains = DeviceNetworkEvents_
  | distinct Domain
  | summarize make_list(Domain);

Stage 1: `source`

let DeviceNetworkEvents_

Stage 2: `source`

let DeviceNetworkEventDomains

Stage 3: `source`

ThreatIntelIndicators

Stage 4: `extend`

extend IndicatorType

Stage 5: `where`

where IndicatorType =~ "domain-name"

Stage 6: `extend`

extend DomainName

Stage 7: `where`

where TimeGenerated >= ago(1209600s)

Stage 8: `extend`

extend IndicatorId

Stage 9: `where`

where DomainName =~ "DeviceNetworkEventDomains"

Stage 10: `summarize`

summarize LatestIndicatorTime by Id, ObservableValue

Stage 11: `where`

where (isempty(ValidUntil) or ValidUntil > now())

Stage 12: `extend`

extend Description

Stage 13: `extend`

extend TrafficLightProtocolLevel

Stage 14: `where`

where not (Description contains "State: falsepos;") and not (Description contains "State: inactive;")

Stage 15: `project-reorder`

project-reorder

Stage 16: `join`

join kind=innerunique (DeviceNetworkEvents_) on DomainName, Domain

Stage 17: `where`

where DeviceNetworkEvents_TimeGenerated < ValidUntil

Stage 18: `summarize`

summarize DeviceNetworkEvents_TimeGenerated by IndicatorId

Stage 19: `project`

project ActionType, Confidence, Description, DeviceId, DeviceName, DeviceNetworkEvents_TimeGenerated, IndicatorId, InitiatingProcessAccountUpn, InitiatingProcessCommandLine, RemoteIP, RemotePort, Tags, TrafficLightProtocolLevel, Url

Stage 20: `extend`

extend Name, UPNSuffix

Stage 21: `extend`

extend UserPrincipalName, timestamp

Exclusions

The rule actively suppresses these predicates.

Field	Kind	Excluded values	Search
`Description`	contains	`State: falsepos;`	`excludes:Description` `field:"Description" value:"State: falsepos;"`
`Description`	contains	`State: inactive;`	`excludes:Description` `field:"Description" value:"State: inactive;"`
`ActionType`	match	`ConnectionFailed`	`excludes:ActionType` `field:"ActionType" value:"ConnectionFailed"`

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`DeviceNetworkEvents_TimeGenerated`	cross_field_compare	`ValidUntil` transforms: `op:lt` corpus 2 (kusto 2)	`field:"DeviceNetworkEvents_TimeGenerated" kind:cross_field_compare value:"ValidUntil"`
`Domain`	is_not_null	(no value, null check)	`field:"Domain" kind:is_not_null`
`DomainName`	in	`DeviceNetworkEventDomains`	`field:"DomainName" kind:in value:"DeviceNetworkEventDomains"`
`IndicatorType`	eq	`domain-name` corpus 11 (kusto 11)	`field:"IndicatorType" kind:eq value:"domain-name"`
`RemoteUrl`	is_not_null	(no value, null check)	`field:"DestinationHostname" kind:is_not_null`
`ValidUntil`	is_null	(no value, null check)	`field:"ValidUntil" kind:is_null`

Output fields

These fields are emitted when the rule matches.

Field	Source
`ActionType`	`project`
`Confidence`	`project`
`Description`	`project`
`DeviceId`	`project`
`DeviceName`	`project`
`DeviceNetworkEvents_TimeGenerated`	`project`
`IndicatorId`	`project`
`InitiatingProcessAccountUpn`	`project`
`InitiatingProcessCommandLine`	`project`
`RemoteIP`	`project`
`RemotePort`	`project`
`Tags`	`project`
`TrafficLightProtocolLevel`	`project`
`Url`	`project`
`Name`	`extend`
`UPNSuffix`	`extend`
`UserPrincipalName`	`extend`
`timestamp`	`extend`

TI Map Domain Entity to DeviceNetworkEvents

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Parameters

Let binding: DeviceNetworkEvents_ used in Stages 1, 16

Let binding: DeviceNetworkEventDomains used in Stages 2, 9

Stage 1: source

Stage 2: source

Stage 3: source

Stage 4: extend

Stage 5: where

Stage 6: extend

Stage 7: where

Stage 8: extend

Stage 9: where

Stage 10: summarize

Stage 11: where

Stage 12: extend

Stage 13: extend

Stage 14: where

Stage 15: project-reorder

Stage 16: join

Stage 17: where

Stage 18: summarize

Stage 19: project

Stage 20: extend

Stage 21: extend