Microsoft Sentinel Analytic Rules
cloudbrothers.infoAzure Sentinel RepoToggle Dark/Light/Auto modeToggle Dark/Light/Auto modeToggle Dark/Light/Auto modeBack to homepage

Cisco SEG - Malicious attachment not blocked

Back
Id236e872c-31d1-4b45-ac2a-fda3af465c97
RulenameCisco SEG - Malicious attachment not blocked
DescriptionDetects mails with malicious attachments which were not blocked.
SeverityHigh
TacticsInitialAccess
TechniquesT1566
Required data connectorsCefAma
KindScheduled
Query frequency10m
Query period10m
Trigger threshold0
Trigger operatorgt
Source Urihttps://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGMaliciousAttachmentNotBlocked.yaml
Version1.0.3
Arm template236e872c-31d1-4b45-ac2a-fda3af465c97.json
Deploy To Azure
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
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: Name
    columnName: AccountCustomEntity
queryFrequency: 10m
name: Cisco SEG - Malicious attachment not blocked
kind: Scheduled
tactics:
- InitialAccess
triggerThreshold: 0
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
triggerOperator: gt
queryPeriod: 10m
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGMaliciousAttachmentNotBlocked.yaml
severity: High
status: Available
id: 236e872c-31d1-4b45-ac2a-fda3af465c97
requiredDataConnectors:
- connectorId: CefAma
  dataTypes:
  - CommonSecurityLog
version: 1.0.3
description: |
    'Detects mails with malicious attachments which were not blocked.'
{
  "$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": "1.0.3",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}