Detection rules › Kusto

Ubiquiti - connection to non-corporate DNS server

Status
available
Severity
medium
Time window
1h
Source
github.com/Azure/Azure-Sentinel

'Detects connections to non-corporate DNS servers.'

MITRE ATT&CK coverage

TacticTechniques
Command & Control
Exfiltration

Rule body

id: fe232837-9bdc-4e2b-8c08-cdac2610eed3
name: Ubiquiti - connection to non-corporate DNS server
description: |
  'Detects connections to non-corporate DNS servers.'
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: CustomLogsAma
    dataTypes:
      - Ubiquiti_CL
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - CommandAndControl
  - Exfiltration
relevantTechniques:
  - T1572
  - T1041
query: |
  let corp_dns = dynamic(['127.0.0.2']);
  UbiquitiAuditEvent
  | where DstPortNumber == '53'
  | where DstIpAddr !in (corp_dns)
  | extend IPCustomEntity = SrcIpAddr
entityMappings:
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: IPCustomEntity
version: 1.0.2
kind: Scheduled

Stages and Predicates

Parameters

let corp_dns = dynamic(['127.0.0.2']);

Stage 1: source

UbiquitiAuditEvent

Stage 2: where

| where DstPortNumber == '53'

Stage 3: where

| where DstIpAddr !in (corp_dns)

Stage 4: extend

| extend IPCustomEntity = SrcIpAddr

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
DstIpAddreqcorp_dnsexcludes:DstIpAddr field:"DstIpAddr" value:"corp_dns"

Indicators

These rows show field, operator, and value matches.

Output fields

These fields are emitted when the rule matches.

FieldSource
IPCustomEntityextend