NGINX - Core Dump

NGINXHTTPServer
| where EventType =~ "ErrorLog"
| where EventMessage contains 'exited on signal 6 (core dumped)'
| extend ProcessIdCustomEntity = ProcessId

relevantTechniques:
- T1499
name: NGINX - Core Dump
requiredDataConnectors:
- dataTypes:
  - NGINXHTTPServer
  connectorId: NGINXHTTPServer
- dataTypes:
  - NGINX_CL
  connectorId: CustomLogsAma
entityMappings:
- fieldMappings:
  - identifier: ProcessId
    columnName: ProcessIdCustomEntity
  entityType: Process
triggerThreshold: 0
id: 9a7f5a97-354b-4eac-b407-a1cc7fc4b4ec
tactics:
- Impact
version: 1.0.2
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/NGINX HTTP Server/Analytic Rules/NGINXCoreDump.yaml
queryPeriod: 10m
kind: Scheduled
queryFrequency: 10m
severity: High
status: Available
description: |
    'Detects a core dump of a crashing Nginx worker process, which could be a signal of a serious problem or exploitation attempts.'
query: |
  NGINXHTTPServer
  | where EventType =~ "ErrorLog"
  | where EventMessage contains 'exited on signal 6 (core dumped)'
  | extend ProcessIdCustomEntity = ProcessId  
triggerOperator: gt

{
  "$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/9a7f5a97-354b-4eac-b407-a1cc7fc4b4ec')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/9a7f5a97-354b-4eac-b407-a1cc7fc4b4ec')]",
      "properties": {
        "alertRuleTemplateName": "9a7f5a97-354b-4eac-b407-a1cc7fc4b4ec",
        "customDetails": null,
        "description": "'Detects a core dump of a crashing Nginx worker process, which could be a signal of a serious problem or exploitation attempts.'\n",
        "displayName": "NGINX - Core Dump",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Process",
            "fieldMappings": [
              {
                "columnName": "ProcessIdCustomEntity",
                "identifier": "ProcessId"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/NGINX HTTP Server/Analytic Rules/NGINXCoreDump.yaml",
        "query": "NGINXHTTPServer\n| where EventType =~ \"ErrorLog\"\n| where EventMessage contains 'exited on signal 6 (core dumped)'\n| extend ProcessIdCustomEntity = ProcessId\n",
        "queryFrequency": "PT10M",
        "queryPeriod": "PT10M",
        "severity": "High",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Impact"
        ],
        "techniques": [
          "T1499"
        ],
        "templateVersion": "1.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}