Detection rules › Kusto

Digital Guardian - Possible SMTP protocol abuse

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

'Detects possible SMTP protocol abuse.'

MITRE ATT&CK coverage

Rule body

id: a374a933-f6c4-4200-8682-70402a9054dd
name: Digital Guardian - Possible SMTP protocol abuse
description: |
  'Detects possible SMTP protocol abuse.'
severity: High
status: Available
requiredDataConnectors:
  - connectorId: SyslogAma
    datatypes:
      - Syslog
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Exfiltration
relevantTechniques:
  - T1048
query: |
  DigitalGuardianDLPEvent
  | where NetworkApplicationProtocol =~ 'SMTP'
  | where DstPortNumber != 25
  | extend AccountCustomEntity = SrcUserName
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: AccountCustomEntity
version: 1.0.2
kind: Scheduled

Stages and Predicates

Stage 1: source

DigitalGuardianDLPEvent

Stage 2: where

| where NetworkApplicationProtocol =~ 'SMTP'

Stage 3: where

| where DstPortNumber != 25

Stage 4: extend

| extend AccountCustomEntity = SrcUserName

Indicators

These rows show field, operator, and value matches.

Output fields

These fields are emitted when the rule matches.

FieldSource
AccountCustomEntityextend