Detection rules › Kusto

Cisco Duo - New access device

Status
available
Severity
medium
Time window
14d
Group by
UserName
Source
github.com/Azure/Azure-Sentinel

'Detects new access device.'

MITRE ATT&CK coverage

TacticTechniques
Initial Access

Rule body

id: f05271b6-26a5-49cf-ad73-4a202fba6eb6
name: Cisco Duo - New access device
description: |
  'Detects new access device.'
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: CiscoDuoAuthConnectorDefinition
    dataTypes:
      - DuoAuthentication_CL
queryFrequency: 1h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - InitialAccess
relevantTechniques:
  - T1078
query: |
  DuoAuthentication_CL
  | where Result =~ 'success'
  | where isnotempty(AccessDeviceIp)
  | summarize dvc_ip = make_set(AccessDeviceIp) by UserName
  | join (DuoAuthentication_CL
          | where Result =~ 'success') on UserName
  | where dvc_ip !has AccessDeviceIp
  | extend IPCustomEntity = AccessDeviceIp, AccountCustomEntity = UserName
entityMappings:
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: IPCustomEntity
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: AccountCustomEntity
version: 1.0.1
kind: Scheduled

Stages and Predicates

Stage 1: source

DuoAuthentication_CL

Stage 2: where

| where Result =~ 'success'

Stage 3: where

| where isnotempty(AccessDeviceIp)

Stage 4: summarize

| summarize dvc_ip = make_set(AccessDeviceIp) by UserName

Stage 5: join

| join (DuoAuthentication_CL
        | where Result =~ 'success') on UserName

Stage 6: where

| where dvc_ip !has AccessDeviceIp

Stage 7: extend

| extend IPCustomEntity = AccessDeviceIp, AccountCustomEntity = UserName

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
AccessDeviceIpis_not_null
  • (no value, null check)
field:"AccessDeviceIp" kind:is_not_null
Resulteq
  • success
field:"Result" kind:eq value:"success"
dvc_ipcross_field_compare
  • AccessDeviceIp transforms: op:match
field:"dvc_ip" kind:cross_field_compare value:"AccessDeviceIp"

Output fields

These fields are emitted when the rule matches.

FieldSource
UserNamesummarize
dvc_ipsummarize
AccountCustomEntityextend
IPCustomEntityextend