Certified Pre-Owned - TGTs requested with certificate authentication
Id | b838a13c-052e-45b8-a5ac-7d3eb62efa11 |
Rulename | Certified Pre-Owned - TGTs requested with certificate authentication |
Description | This query identifies someone using machine certificates to request Kerberos Ticket Granting Tickets (TGTs). |
Severity | Medium |
Tactics | DefenseEvasion |
Techniques | T1036 |
Required data connectors | SecurityEvents WindowsSecurityEvents |
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/FalconFriday/Analytic Rules/CertifiedPreOwned-TGTs-requested.yaml |
Version | 1.0.1 |
Arm template | b838a13c-052e-45b8-a5ac-7d3eb62efa11.json |
let timeframe=1h;
SecurityEvent
| where TimeGenerated >= ago(timeframe)
| where EventID == 4768
| project TimeGenerated, Computer, TargetAccount, EventData=parse_xml(EventData)
| mv-apply d=EventData.EventData.Data on
(
where d["@Name"]=="CertIssuerName"
| project CIN=tostring(d["#text"])
)
| where not(isempty(CIN))
// <DECISION - 1>
// In some environments, we see a lot of certs starting with a sid and containing live.com. Comment out the next line if you have that as well.
//| where not(CIN startswith "S-1-")
// <DECISION - 2>
// If you're seeing a significant number of machine accounts, it might be due to 802.1X or SCCM. https://twitter.com/MagnusMOD/status/1407800853088591872?s=20.
// The following line allows you to filter out all endpoints. This does introduce a blindspot, and you need a custom function which provides data about (on-prem) AD machines.
// Alternatively, you can use DeviceInfo, if you're ingesting that data from MDE.
| parse CIN with "CN=" MachineName
//| join kind=leftouter MyCustomLookupFunction on $left.MachineName == $right.CN
//| where not(OperatingSystem startswith "Windows 10")
name: Certified Pre-Owned - TGTs requested with certificate authentication
version: 1.0.1
severity: Medium
queryFrequency: 1h
triggerOperator: gt
relevantTechniques:
- T1036
status: Available
description: |
This query identifies someone using machine certificates to request Kerberos Ticket Granting Tickets (TGTs).
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/FalconFriday/Analytic Rules/CertifiedPreOwned-TGTs-requested.yaml
requiredDataConnectors:
- connectorId: SecurityEvents
dataTypes:
- SecurityEvent
- connectorId: WindowsSecurityEvents
dataTypes:
- SecurityEvent
entityMappings:
- fieldMappings:
- identifier: FullName
columnName: TargetAccount
entityType: Account
tactics:
- DefenseEvasion
queryPeriod: 1h
query: |
let timeframe=1h;
SecurityEvent
| where TimeGenerated >= ago(timeframe)
| where EventID == 4768
| project TimeGenerated, Computer, TargetAccount, EventData=parse_xml(EventData)
| mv-apply d=EventData.EventData.Data on
(
where d["@Name"]=="CertIssuerName"
| project CIN=tostring(d["#text"])
)
| where not(isempty(CIN))
// <DECISION - 1>
// In some environments, we see a lot of certs starting with a sid and containing live.com. Comment out the next line if you have that as well.
//| where not(CIN startswith "S-1-")
// <DECISION - 2>
// If you're seeing a significant number of machine accounts, it might be due to 802.1X or SCCM. https://twitter.com/MagnusMOD/status/1407800853088591872?s=20.
// The following line allows you to filter out all endpoints. This does introduce a blindspot, and you need a custom function which provides data about (on-prem) AD machines.
// Alternatively, you can use DeviceInfo, if you're ingesting that data from MDE.
| parse CIN with "CN=" MachineName
//| join kind=leftouter MyCustomLookupFunction on $left.MachineName == $right.CN
//| where not(OperatingSystem startswith "Windows 10")
kind: Scheduled
triggerThreshold: 0
id: b838a13c-052e-45b8-a5ac-7d3eb62efa11
{
"$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/b838a13c-052e-45b8-a5ac-7d3eb62efa11')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/b838a13c-052e-45b8-a5ac-7d3eb62efa11')]",
"properties": {
"alertRuleTemplateName": "b838a13c-052e-45b8-a5ac-7d3eb62efa11",
"customDetails": null,
"description": "This query identifies someone using machine certificates to request Kerberos Ticket Granting Tickets (TGTs).\n",
"displayName": "Certified Pre-Owned - TGTs requested with certificate authentication",
"enabled": true,
"entityMappings": [
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "TargetAccount",
"identifier": "FullName"
}
]
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/FalconFriday/Analytic Rules/CertifiedPreOwned-TGTs-requested.yaml",
"query": "let timeframe=1h;\nSecurityEvent\n| where TimeGenerated >= ago(timeframe)\n| where EventID == 4768\n| project TimeGenerated, Computer, TargetAccount, EventData=parse_xml(EventData)\n| mv-apply d=EventData.EventData.Data on\n(\n where d[\"@Name\"]==\"CertIssuerName\"\n | project CIN=tostring(d[\"#text\"])\n)\n| where not(isempty(CIN))\n// <DECISION - 1>\n// In some environments, we see a lot of certs starting with a sid and containing live.com. Comment out the next line if you have that as well.\n//| where not(CIN startswith \"S-1-\")\n// <DECISION - 2>\n// If you're seeing a significant number of machine accounts, it might be due to 802.1X or SCCM. https://twitter.com/MagnusMOD/status/1407800853088591872?s=20.\n// The following line allows you to filter out all endpoints. This does introduce a blindspot, and you need a custom function which provides data about (on-prem) AD machines.\n// Alternatively, you can use DeviceInfo, if you're ingesting that data from MDE.\n| parse CIN with \"CN=\" MachineName\n//| join kind=leftouter MyCustomLookupFunction on $left.MachineName == $right.CN\n//| where not(OperatingSystem startswith \"Windows 10\")\n",
"queryFrequency": "PT1H",
"queryPeriod": "PT1H",
"severity": "Medium",
"status": "Available",
"subTechniques": [],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"DefenseEvasion"
],
"techniques": [
"T1036"
],
"templateVersion": "1.0.1",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}