let img_ =
VMwareESXi
| where SyslogMessage has ('Matched discovered VM')
| extend DstHostname = extract(@'vim.VirtualMachine\S+,(.*?)\]', 1, SyslogMessage)
| extend kImageName = extract(@'ds:///vmfs/volumes/(.*)/(.*?),', 2, SyslogMessage)
| summarize img_lst = makeset(kImageName) by DstHostname;
VMwareESXi
| where SyslogMessage has ('Matched discovered VM')
| extend DstHostname = extract(@'vim.VirtualMachine\S+,(.*?)\]', 1, SyslogMessage)
| extend ImageName = extract(@'ds:///vmfs/volumes/(.*)/(.*?),', 2, SyslogMessage)
| join (img_) on DstHostname
| where img_lst !has ImageName
| extend HostCustomEntity = DstHostname
version: 1.0.0
name: VMware ESXi - Unexpected disk image
severity: Medium
queryFrequency: 1h
kind: Scheduled
queryPeriod: 14d
description: |
'Detects unexpected disk image for VM.'
query: |
let img_ =
VMwareESXi
| where SyslogMessage has ('Matched discovered VM')
| extend DstHostname = extract(@'vim.VirtualMachine\S+,(.*?)\]', 1, SyslogMessage)
| extend kImageName = extract(@'ds:///vmfs/volumes/(.*)/(.*?),', 2, SyslogMessage)
| summarize img_lst = makeset(kImageName) by DstHostname;
VMwareESXi
| where SyslogMessage has ('Matched discovered VM')
| extend DstHostname = extract(@'vim.VirtualMachine\S+,(.*?)\]', 1, SyslogMessage)
| extend ImageName = extract(@'ds:///vmfs/volumes/(.*)/(.*?),', 2, SyslogMessage)
| join (img_) on DstHostname
| where img_lst !has ImageName
| extend HostCustomEntity = DstHostname
tactics:
- Impact
triggerOperator: gt
entityMappings:
- entityType: Host
fieldMappings:
- columnName: HostCustomEntity
identifier: FullName
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/VMWareESXi/Analytic Rules/ESXiUnexpectedDiskImage.yaml
requiredDataConnectors:
- connectorId: VMwareESXi
dataTypes:
- VMwareESXi
status: Available
relevantTechniques:
- T1496
id: 395c5560-ddc2-45b2-aafe-2e3f64528d3d
{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"workspace": {
"type": "String"
}
},
"resources": [
{
"id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/395c5560-ddc2-45b2-aafe-2e3f64528d3d')]",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/395c5560-ddc2-45b2-aafe-2e3f64528d3d')]",
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
"kind": "Scheduled",
"apiVersion": "2022-11-01-preview",
"properties": {
"displayName": "VMware ESXi - Unexpected disk image",
"description": "'Detects unexpected disk image for VM.'\n",
"severity": "Medium",
"enabled": true,
"query": "let img_ =\nVMwareESXi\n| where SyslogMessage has ('Matched discovered VM')\n| extend DstHostname = extract(@'vim.VirtualMachine\\S+,(.*?)\\]', 1, SyslogMessage)\n| extend kImageName = extract(@'ds:///vmfs/volumes/(.*)/(.*?),', 2, SyslogMessage)\n| summarize img_lst = makeset(kImageName) by DstHostname;\nVMwareESXi\n| where SyslogMessage has ('Matched discovered VM')\n| extend DstHostname = extract(@'vim.VirtualMachine\\S+,(.*?)\\]', 1, SyslogMessage)\n| extend ImageName = extract(@'ds:///vmfs/volumes/(.*)/(.*?),', 2, SyslogMessage)\n| join (img_) on DstHostname\n| where img_lst !has ImageName\n| extend HostCustomEntity = DstHostname\n",
"queryFrequency": "PT1H",
"queryPeriod": "P14D",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0,
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"Impact"
],
"techniques": [
"T1496"
],
"alertRuleTemplateName": "395c5560-ddc2-45b2-aafe-2e3f64528d3d",
"customDetails": null,
"entityMappings": [
{
"fieldMappings": [
{
"columnName": "HostCustomEntity",
"identifier": "FullName"
}
],
"entityType": "Host"
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/VMWareESXi/Analytic Rules/ESXiUnexpectedDiskImage.yaml",
"templateVersion": "1.0.0",
"status": "Available"
}
}
]
}