Multiple Sources Affected by the Same TI Destination

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Id	4644baf7-3464-45dd-bd9d-e07687e25f81
Rulename	Multiple Sources Affected by the Same TI Destination
Description	Identifies multiple machines trying to reach out to the same destination blocked by TI in Azure Firewall. This can indicate attack on the organization by the same attack group. Configurable Parameters: - Minimum affected threshold - alert only if more than this number of hosts affected. Default is set to 5. - Recommendation is to use the new resource specific logs. If you are using both, the TiTraffic Count will be duplicated.
Severity	Medium
Tactics	Exfiltration CommandAndControl
Techniques	T1041 T1071
Required data connectors	AzureFirewall
Kind	Scheduled
Query frequency	1d
Query period	1d
Trigger threshold	1
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Firewall/Analytic Rules/Azure Firewall - Multiple Sources Affected by the Same TI Destination.yaml
Version	1.1.3
Arm template	4644baf7-3464-45dd-bd9d-e07687e25f81.json

KQL

let RunTime = 1d; 
let StartRunTime = 1d; 
let EndRunTime = StartRunTime - RunTime; 
let MinAffectedThreshold = 5;
union isfuzzy=true
(AzureDiagnostics 
| where TimeGenerated  between (ago(StartRunTime) .. ago(EndRunTime))
| where OperationName == "AzureFirewallThreatIntelLog"
| parse msg_s with * "from " SourceIp ":" SourcePort:int " to " Fqdn ":" DestinationPort:int  "." * "Action: Deny. " ThreatDescription),
(AZFWThreatIntel
| where TimeGenerated between (ago(StartRunTime) .. ago(EndRunTime)))
| summarize TiTrafficCount = count(), dCountSourceIps = dcount(SourceIp), AffectedIps = make_set(SourceIp, 10000) by Fqdn, ThreatDescription
| where array_length(AffectedIps) > MinAffectedThreshold
| mv-expand SourceIp = AffectedIps
| order by TiTrafficCount desc, Fqdn asc, parse_ipv4(tostring(SourceIp)) asc

YAML

queryPeriod: 1d
requiredDataConnectors:
- connectorId: AzureFirewall
  dataTypes:
  - AzureDiagnostics
  - AZFWThreatIntel
triggerThreshold: 1
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Firewall/Analytic Rules/Azure Firewall - Multiple Sources Affected by the Same TI Destination.yaml
tactics:
- Exfiltration
- CommandAndControl
triggerOperator: gt
severity: Medium
name: Multiple Sources Affected by the Same TI Destination
relevantTechniques:
- T1041
- T1071
query: |
  let RunTime = 1d; 
  let StartRunTime = 1d; 
  let EndRunTime = StartRunTime - RunTime; 
  let MinAffectedThreshold = 5;
  union isfuzzy=true
  (AzureDiagnostics 
  | where TimeGenerated  between (ago(StartRunTime) .. ago(EndRunTime))
  | where OperationName == "AzureFirewallThreatIntelLog"
  | parse msg_s with * "from " SourceIp ":" SourcePort:int " to " Fqdn ":" DestinationPort:int  "." * "Action: Deny. " ThreatDescription),
  (AZFWThreatIntel
  | where TimeGenerated between (ago(StartRunTime) .. ago(EndRunTime)))
  | summarize TiTrafficCount = count(), dCountSourceIps = dcount(SourceIp), AffectedIps = make_set(SourceIp, 10000) by Fqdn, ThreatDescription
  | where array_length(AffectedIps) > MinAffectedThreshold
  | mv-expand SourceIp = AffectedIps
  | order by TiTrafficCount desc, Fqdn asc, parse_ipv4(tostring(SourceIp)) asc  
queryFrequency: 1d
id: 4644baf7-3464-45dd-bd9d-e07687e25f81
status: Available
kind: Scheduled
entityMappings:
- fieldMappings:
  - columnName: SourceIp
    identifier: Address
  entityType: IP
- fieldMappings:
  - columnName: Fqdn
    identifier: Url
  entityType: URL
version: 1.1.3
description: |
  'Identifies multiple machines trying to reach out to the same destination blocked by TI in Azure Firewall. This can indicate attack on the organization by the same attack group.

  Configurable Parameters:

  - Minimum affected threshold - alert only if more than this number of hosts affected. Default is set to 5.
  - Recommendation is to use the new resource specific logs. If you are using both, the TiTraffic Count will be duplicated.'

ARM

{
  "$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/4644baf7-3464-45dd-bd9d-e07687e25f81')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/4644baf7-3464-45dd-bd9d-e07687e25f81')]",
      "properties": {
        "alertRuleTemplateName": "4644baf7-3464-45dd-bd9d-e07687e25f81",
        "customDetails": null,
        "description": "'Identifies multiple machines trying to reach out to the same destination blocked by TI in Azure Firewall. This can indicate attack on the organization by the same attack group.\n\nConfigurable Parameters:\n\n- Minimum affected threshold - alert only if more than this number of hosts affected. Default is set to 5.\n- Recommendation is to use the new resource specific logs. If you are using both, the TiTraffic Count will be duplicated.'\n",
        "displayName": "Multiple Sources Affected by the Same TI Destination",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "SourceIp",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "URL",
            "fieldMappings": [
              {
                "columnName": "Fqdn",
                "identifier": "Url"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Firewall/Analytic Rules/Azure Firewall - Multiple Sources Affected by the Same TI Destination.yaml",
        "query": "let RunTime = 1d; \nlet StartRunTime = 1d; \nlet EndRunTime = StartRunTime - RunTime; \nlet MinAffectedThreshold = 5;\nunion isfuzzy=true\n(AzureDiagnostics \n| where TimeGenerated  between (ago(StartRunTime) .. ago(EndRunTime))\n| where OperationName == \"AzureFirewallThreatIntelLog\"\n| parse msg_s with * \"from \" SourceIp \":\" SourcePort:int \" to \" Fqdn \":\" DestinationPort:int  \".\" * \"Action: Deny. \" ThreatDescription),\n(AZFWThreatIntel\n| where TimeGenerated between (ago(StartRunTime) .. ago(EndRunTime)))\n| summarize TiTrafficCount = count(), dCountSourceIps = dcount(SourceIp), AffectedIps = make_set(SourceIp, 10000) by Fqdn, ThreatDescription\n| where array_length(AffectedIps) > MinAffectedThreshold\n| mv-expand SourceIp = AffectedIps\n| order by TiTrafficCount desc, Fqdn asc, parse_ipv4(tostring(SourceIp)) asc\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CommandAndControl",
          "Exfiltration"
        ],
        "techniques": [
          "T1041",
          "T1071"
        ],
        "templateVersion": "1.1.3",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 1
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}