Excessive Amount of Denied Connections from a Single Source
Id | 3d645a88-2724-41a7-adea-db74c439cf79 |
Rulename | 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. |
Severity | Medium |
Tactics | Impact |
Techniques | T1499 |
Required data connectors | SophosXGFirewall SyslogAma |
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/Sophos XG Firewall/Analytic Rules/ExcessiveAmountofDeniedConnectionsfromASingleSource.yaml |
Version | 1.0.3 |
Arm template | 3d645a88-2724-41a7-adea-db74c439cf79.json |
let threshold = 5000;
SophosXGFirewall
| where Log_Type =~ "Firewall" and Status =~ "Deny"
| summarize count() by Src_IP, bin(TimeGenerated,5m)
| where count_ > threshold
name: Excessive Amount of Denied Connections from a Single Source
version: 1.0.3
severity: Medium
queryFrequency: 1h
triggerOperator: gt
relevantTechniques:
- T1499
status: Available
description: |
'This creates an incident in the event that a single source IP address generates a excessive amount of denied connections.'
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Sophos XG Firewall/Analytic Rules/ExcessiveAmountofDeniedConnectionsfromASingleSource.yaml
requiredDataConnectors:
- connectorId: SophosXGFirewall
dataTypes:
- Syslog
- connectorId: SyslogAma
datatypes:
- Syslog
entityMappings:
- fieldMappings:
- identifier: Address
columnName: Src_IP
entityType: IP
tactics:
- Impact
queryPeriod: 1h
query: |
let threshold = 5000;
SophosXGFirewall
| where Log_Type =~ "Firewall" and Status =~ "Deny"
| summarize count() by Src_IP, bin(TimeGenerated,5m)
| where count_ > threshold
kind: Scheduled
triggerThreshold: 0
id: 3d645a88-2724-41a7-adea-db74c439cf79
{
"$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/3d645a88-2724-41a7-adea-db74c439cf79')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/3d645a88-2724-41a7-adea-db74c439cf79')]",
"properties": {
"alertRuleTemplateName": "3d645a88-2724-41a7-adea-db74c439cf79",
"customDetails": null,
"description": "'This creates an incident in the event that a single source IP address generates a excessive amount of denied connections.'\n",
"displayName": "Excessive Amount of Denied Connections from a Single Source",
"enabled": true,
"entityMappings": [
{
"entityType": "IP",
"fieldMappings": [
{
"columnName": "Src_IP",
"identifier": "Address"
}
]
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Sophos XG Firewall/Analytic Rules/ExcessiveAmountofDeniedConnectionsfromASingleSource.yaml",
"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",
"queryFrequency": "PT1H",
"queryPeriod": "PT1H",
"severity": "Medium",
"status": "Available",
"subTechniques": [],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"Impact"
],
"techniques": [
"T1499"
],
"templateVersion": "1.0.3",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}