Cisco SEG - Malicious attachment not blocked

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Id	236e872c-31d1-4b45-ac2a-fda3af465c97
Rulename	Cisco SEG - Malicious attachment not blocked
Description	Detects mails with malicious attachments which were not blocked.
Severity	High
Tactics	InitialAccess
Techniques	T1566
Required data connectors	CefAma CiscoSEG CiscoSEGAma
Kind	Scheduled
Query frequency	10m
Query period	10m
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGMaliciousAttachmentNotBlocked.yaml
Version	1.0.2
Arm template	236e872c-31d1-4b45-ac2a-fda3af465c97.json

KQL

CiscoSEGEvent
| where NetworkDirection =~ 'Incoming'
| where SimplifiedDeviceAction =~ 'DELIVERED'
| where tostring(AdditionalFields) has 'ESAAMPVerdict'
| extend amp_verdict = extract(@'ESAAMPVerdict":"(NOT_EVALUATED|CLEAN|FA_PENDING|UNKNOWN|SKIPPED|UNSCANNABLE|LOW_RISK|MALICIOUS)"', 1, tostring(AdditionalFields))
| where amp_verdict =~ 'MALICIOUS'
| extend AccountCustomEntity = DstUserName

YAML

query: |
  CiscoSEGEvent
  | where NetworkDirection =~ 'Incoming'
  | where SimplifiedDeviceAction =~ 'DELIVERED'
  | where tostring(AdditionalFields) has 'ESAAMPVerdict'
  | extend amp_verdict = extract(@'ESAAMPVerdict":"(NOT_EVALUATED|CLEAN|FA_PENDING|UNKNOWN|SKIPPED|UNSCANNABLE|LOW_RISK|MALICIOUS)"', 1, tostring(AdditionalFields))
  | where amp_verdict =~ 'MALICIOUS'
  | extend AccountCustomEntity = DstUserName  
relevantTechniques:
- T1566
name: Cisco SEG - Malicious attachment not blocked
severity: High
triggerThreshold: 0
description: |
    'Detects mails with malicious attachments which were not blocked.'
status: Available
triggerOperator: gt
tactics:
- InitialAccess
entityMappings:
- fieldMappings:
  - columnName: AccountCustomEntity
    identifier: Name
  entityType: Account
requiredDataConnectors:
- connectorId: CiscoSEG
  dataTypes:
  - CiscoSEGEvent
- connectorId: CiscoSEGAma
  dataTypes:
  - CiscoSEGEvent
- connectorId: CefAma
  dataTypes:
  - CommonSecurityLog
id: 236e872c-31d1-4b45-ac2a-fda3af465c97
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGMaliciousAttachmentNotBlocked.yaml
queryPeriod: 10m
queryFrequency: 10m
version: 1.0.2
kind: Scheduled

ARM

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2024-01-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/236e872c-31d1-4b45-ac2a-fda3af465c97')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/236e872c-31d1-4b45-ac2a-fda3af465c97')]",
      "properties": {
        "alertRuleTemplateName": "236e872c-31d1-4b45-ac2a-fda3af465c97",
        "customDetails": null,
        "description": "'Detects mails with malicious attachments which were not blocked.'\n",
        "displayName": "Cisco SEG - Malicious attachment not blocked",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "AccountCustomEntity",
                "identifier": "Name"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGMaliciousAttachmentNotBlocked.yaml",
        "query": "CiscoSEGEvent\n| where NetworkDirection =~ 'Incoming'\n| where SimplifiedDeviceAction =~ 'DELIVERED'\n| where tostring(AdditionalFields) has 'ESAAMPVerdict'\n| extend amp_verdict = extract(@'ESAAMPVerdict\":\"(NOT_EVALUATED|CLEAN|FA_PENDING|UNKNOWN|SKIPPED|UNSCANNABLE|LOW_RISK|MALICIOUS)\"', 1, tostring(AdditionalFields))\n| where amp_verdict =~ 'MALICIOUS'\n| extend AccountCustomEntity = DstUserName\n",
        "queryFrequency": "PT10M",
        "queryPeriod": "PT10M",
        "severity": "High",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "InitialAccess"
        ],
        "techniques": [
          "T1566"
        ],
        "templateVersion": "1.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}