Cisco SEG - Suspicious sender domain
Id | ef0a253c-95b5-48e1-8ebc-dbeb073b9338 |
Rulename | Cisco SEG - Suspicious sender domain |
Description | Detects suspicious sender domain age. |
Severity | Medium |
Tactics | InitialAccess |
Techniques | T1566 |
Required data connectors | CefAma |
Kind | Scheduled |
Query frequency | 1h |
Query period | 1h |
Trigger threshold | 0 |
Trigger operator | gt |
Source Uri | https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGSuspiciousSenderDomain.yaml |
Version | 1.0.3 |
Arm template | ef0a253c-95b5-48e1-8ebc-dbeb073b9338.json |
CiscoSEGEvent
| where NetworkDirection =~ 'Incoming'
| extend rec_domain = extract(@'@(.*)', 1, DstUserName)
| extend s_domain = extract(@'@(.*)', 1, SrcUserName)
| where s_domain != rec_domain
| where tostring(AdditionalFields) has 'ESASDRDomainAge'
| extend domain_age = extract(@'ESASDRDomainAge":"(.*days)"', 1, tostring(AdditionalFields))
| extend yy = toint(extract(@'(\d+)\syears', 1, domain_age))
| extend mm = toint(extract(@'(\d+)\smonths', 1, domain_age))
| extend dd = toint(extract(@'(\d+)\sdays', 1, domain_age))
| where isempty(yy)
| where isempty(mm) or mm <= 2
| extend AccountCustomEntity = SrcUserName
entityMappings:
- entityType: Account
fieldMappings:
- identifier: Name
columnName: AccountCustomEntity
queryFrequency: 1h
name: Cisco SEG - Suspicious sender domain
kind: Scheduled
tactics:
- InitialAccess
triggerThreshold: 0
query: |
CiscoSEGEvent
| where NetworkDirection =~ 'Incoming'
| extend rec_domain = extract(@'@(.*)', 1, DstUserName)
| extend s_domain = extract(@'@(.*)', 1, SrcUserName)
| where s_domain != rec_domain
| where tostring(AdditionalFields) has 'ESASDRDomainAge'
| extend domain_age = extract(@'ESASDRDomainAge":"(.*days)"', 1, tostring(AdditionalFields))
| extend yy = toint(extract(@'(\d+)\syears', 1, domain_age))
| extend mm = toint(extract(@'(\d+)\smonths', 1, domain_age))
| extend dd = toint(extract(@'(\d+)\sdays', 1, domain_age))
| where isempty(yy)
| where isempty(mm) or mm <= 2
| extend AccountCustomEntity = SrcUserName
relevantTechniques:
- T1566
triggerOperator: gt
queryPeriod: 1h
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGSuspiciousSenderDomain.yaml
severity: Medium
status: Available
id: ef0a253c-95b5-48e1-8ebc-dbeb073b9338
requiredDataConnectors:
- connectorId: CefAma
dataTypes:
- CommonSecurityLog
version: 1.0.3
description: |
'Detects suspicious sender domain age.'
{
"$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/ef0a253c-95b5-48e1-8ebc-dbeb073b9338')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/ef0a253c-95b5-48e1-8ebc-dbeb073b9338')]",
"properties": {
"alertRuleTemplateName": "ef0a253c-95b5-48e1-8ebc-dbeb073b9338",
"customDetails": null,
"description": "'Detects suspicious sender domain age.'\n",
"displayName": "Cisco SEG - Suspicious sender domain",
"enabled": true,
"entityMappings": [
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "AccountCustomEntity",
"identifier": "Name"
}
]
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGSuspiciousSenderDomain.yaml",
"query": "CiscoSEGEvent\n| where NetworkDirection =~ 'Incoming'\n| extend rec_domain = extract(@'@(.*)', 1, DstUserName)\n| extend s_domain = extract(@'@(.*)', 1, SrcUserName)\n| where s_domain != rec_domain\n| where tostring(AdditionalFields) has 'ESASDRDomainAge'\n| extend domain_age = extract(@'ESASDRDomainAge\":\"(.*days)\"', 1, tostring(AdditionalFields))\n| extend yy = toint(extract(@'(\\d+)\\syears', 1, domain_age))\n| extend mm = toint(extract(@'(\\d+)\\smonths', 1, domain_age))\n| extend dd = toint(extract(@'(\\d+)\\sdays', 1, domain_age))\n| where isempty(yy)\n| where isempty(mm) or mm <= 2\n| extend AccountCustomEntity = SrcUserName\n",
"queryFrequency": "PT1H",
"queryPeriod": "PT1H",
"severity": "Medium",
"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"
}
]
}