Mimecast Secure Email Gateway - Spam Event Thread

Back


Id	df1b9377-5c29-4928-872f-9934a6b4f611
Rulename	Mimecast Secure Email Gateway - Spam Event Thread
Description	Detects threat from spam event thread protection logs
Severity	Low
Tactics	Discovery
Techniques	T1083
Required data connectors	MimecastSIEMAPI
Kind	Scheduled
Query frequency	5m
Query period	15m
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/MimecastSEG/Analytic Rules/MimecastSIEM_Spam_Event.yaml
Version	1.0.0
Arm template	df1b9377-5c29-4928-872f-9934a6b4f611.json

KQL

MimecastSIEM_CL| where mimecastEventId_s=="mail_spameventthread"

YAML

id: df1b9377-5c29-4928-872f-9934a6b4f611
triggerThreshold: 0
eventGroupingSettings:
  aggregationKind: SingleAlert
suppressionEnabled: false
severity: Low
customDetails:
  MsgId: MsgId_s
  SenderDomain: SenderDomain_s
  headerFrom: headerFrom_s
  Route: Route_s
  SourceIP: SourceIP
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/MimecastSEG/Analytic Rules/MimecastSIEM_Spam_Event.yaml
relevantTechniques:
- T1083
requiredDataConnectors:
- connectorId: MimecastSIEMAPI
  dataTypes:
  - MimecastSIEM_CL
entityMappings:
- fieldMappings:
  - identifier: Sender
    columnName: Sender_s
  - identifier: Recipient
    columnName: Recipient_s
  - identifier: Subject
    columnName: Subject_s
  entityType: MailMessage
version: 1.0.0
query: MimecastSIEM_CL| where mimecastEventId_s=="mail_spameventthread"
queryPeriod: 15m
triggerOperator: gt
tactics:
- Discovery
enabled: true
suppressionDuration: 5h
incidentConfiguration:
  groupingConfiguration:
    enabled: true
    matchingMethod: AllEntities
    lookbackDuration: 1d
    reopenClosedIncident: false
  createIncident: true
description: Detects threat from spam event thread protection logs
name: Mimecast Secure Email Gateway - Spam Event Thread
kind: Scheduled
queryFrequency: 5m

ARM

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/df1b9377-5c29-4928-872f-9934a6b4f611')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/df1b9377-5c29-4928-872f-9934a6b4f611')]",
      "properties": {
        "alertRuleTemplateName": "df1b9377-5c29-4928-872f-9934a6b4f611",
        "customDetails": {
          "headerFrom": "headerFrom_s",
          "MsgId": "MsgId_s",
          "Route": "Route_s",
          "SenderDomain": "SenderDomain_s",
          "SourceIP": "SourceIP"
        },
        "description": "Detects threat from spam event thread protection logs",
        "displayName": "Mimecast Secure Email Gateway - Spam Event Thread",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "MailMessage",
            "fieldMappings": [
              {
                "columnName": "Sender_s",
                "identifier": "Sender"
              },
              {
                "columnName": "Recipient_s",
                "identifier": "Recipient"
              },
              {
                "columnName": "Subject_s",
                "identifier": "Subject"
              }
            ]
          }
        ],
        "eventGroupingSettings": {
          "aggregationKind": "SingleAlert"
        },
        "incidentConfiguration": {
          "createIncident": true,
          "groupingConfiguration": {
            "enabled": true,
            "lookbackDuration": "P1D",
            "matchingMethod": "AllEntities",
            "reopenClosedIncident": false
          }
        },
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/MimecastSEG/Analytic Rules/MimecastSIEM_Spam_Event.yaml",
        "query": "MimecastSIEM_CL| where mimecastEventId_s==\"mail_spameventthread\"",
        "queryFrequency": "PT5M",
        "queryPeriod": "PT15M",
        "severity": "Low",
        "suppressionDuration": "PT5H",
        "suppressionEnabled": false,
        "tactics": [
          "Discovery"
        ],
        "techniques": [
          "T1083"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}