let threshold = 5000;
SophosXGFirewall
| where Log_Type =~ "Firewall" and Status =~ "Deny"
| summarize count() by Src_IP, bin(TimeGenerated,5m)
| where count_ > threshold
| extend timestamp = TimeGenerated, IPCustomEntity = Src_IP
triggerOperator: gt
version: 1.0.1
query: |
let threshold = 5000;
SophosXGFirewall
| where Log_Type =~ "Firewall" and Status =~ "Deny"
| summarize count() by Src_IP, bin(TimeGenerated,5m)
| where count_ > threshold
| extend timestamp = TimeGenerated, IPCustomEntity = Src_IP
status: Available
entityMappings:
- entityType: IP
fieldMappings:
- columnName: IPCustomEntity
identifier: Address
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Sophos XG Firewall/Analytic Rules/ExcessiveAmountofDeniedConnectionsfromASingleSource.yaml
queryFrequency: 1h
requiredDataConnectors:
- connectorId: SophosXGFirewall
dataTypes:
- Syslog
name: Excessive Amount of Denied Connections from a Single Source
queryPeriod: 1h
severity: Medium
kind: Scheduled
tactics:
- Impact
id: 3d645a88-2724-41a7-adea-db74c439cf79
description: |
'This creates an incident in the event that a single source IP address generates a excessive amount of denied connections.'
relevantTechniques:
- T1499
triggerThreshold: 0
{
"$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/3d645a88-2724-41a7-adea-db74c439cf79')]",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/3d645a88-2724-41a7-adea-db74c439cf79')]",
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
"kind": "Scheduled",
"apiVersion": "2022-11-01-preview",
"properties": {
"displayName": "Excessive Amount of Denied Connections from a Single Source",
"description": "'This creates an incident in the event that a single source IP address generates a excessive amount of denied connections.'\n",
"severity": "Medium",
"enabled": true,
"query": "let threshold = 5000;\nSophosXGFirewall\n| where Log_Type =~ \"Firewall\" and Status =~ \"Deny\"\n| summarize count() by Src_IP, bin(TimeGenerated,5m)\n| where count_ > threshold\n| extend timestamp = TimeGenerated, IPCustomEntity = Src_IP\n",
"queryFrequency": "PT1H",
"queryPeriod": "PT1H",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0,
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"Impact"
],
"techniques": [
"T1499"
],
"alertRuleTemplateName": "3d645a88-2724-41a7-adea-db74c439cf79",
"customDetails": null,
"entityMappings": [
{
"fieldMappings": [
{
"columnName": "IPCustomEntity",
"identifier": "Address"
}
],
"entityType": "IP"
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Sophos XG Firewall/Analytic Rules/ExcessiveAmountofDeniedConnectionsfromASingleSource.yaml",
"status": "Available",
"templateVersion": "1.0.1"
}
}
]
}