let domain_lookBack= 14d;
let timeframe = 1d;
let top_million_list = Cisco_Umbrella
| where EventType == "proxylogs"
| where TimeGenerated > ago(domain_lookBack) and TimeGenerated < ago(timeframe)
| extend Hostname = parse_url(UrlOriginal)["Host"]
| summarize count() by tostring(Hostname)
| top 1000000 by count_
| summarize make_list(Hostname);
Cisco_Umbrella
| where EventType == "proxylogs"
| where TimeGenerated > ago(timeframe)
| extend Hostname = parse_url(UrlOriginal)["Host"]
| where Hostname !in (top_million_list)
| extend Message = "Connect to unpopular website (possible malicious payload delivery)"
| project Message, SrcIpAddr, DstIpAddr,UrlOriginal, TimeGenerated
| extend IPCustomEntity = SrcIpAddr, UrlCustomEntity = UrlOriginal
kind: Scheduled
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/CiscoUmbrella/CiscoUmbrellaConnectionToUnpopularWebsiteDetected.yaml
severity: Medium
name: Cisco Umbrella - Connection to Unpopular Website Detected
entityMappings:
- entityType: URL
fieldMappings:
- columnName: UrlCustomEntity
identifier: Url
- entityType: IP
fieldMappings:
- columnName: IPCustomEntity
identifier: Address
queryFrequency: 1d
triggerThreshold: 0
queryPeriod: 14d
description: |
'Detects first connection to an unpopular website (possible malicious payload delivery).'
id: 75297f62-10a8-4fc1-9b2a-12f25c6f05a7
version: 1.1.1
tactics:
- CommandAndControl
query: |
let domain_lookBack= 14d;
let timeframe = 1d;
let top_million_list = Cisco_Umbrella
| where EventType == "proxylogs"
| where TimeGenerated > ago(domain_lookBack) and TimeGenerated < ago(timeframe)
| extend Hostname = parse_url(UrlOriginal)["Host"]
| summarize count() by tostring(Hostname)
| top 1000000 by count_
| summarize make_list(Hostname);
Cisco_Umbrella
| where EventType == "proxylogs"
| where TimeGenerated > ago(timeframe)
| extend Hostname = parse_url(UrlOriginal)["Host"]
| where Hostname !in (top_million_list)
| extend Message = "Connect to unpopular website (possible malicious payload delivery)"
| project Message, SrcIpAddr, DstIpAddr,UrlOriginal, TimeGenerated
| extend IPCustomEntity = SrcIpAddr, UrlCustomEntity = UrlOriginal
requiredDataConnectors:
- dataTypes:
- Cisco_Umbrella_proxy_CL
connectorId: CiscoUmbrellaDataConnector
triggerOperator: gt
{
"$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/75297f62-10a8-4fc1-9b2a-12f25c6f05a7')]",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/75297f62-10a8-4fc1-9b2a-12f25c6f05a7')]",
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
"kind": "Scheduled",
"apiVersion": "2022-11-01-preview",
"properties": {
"displayName": "Cisco Umbrella - Connection to Unpopular Website Detected",
"description": "'Detects first connection to an unpopular website (possible malicious payload delivery).'\n",
"severity": "Medium",
"enabled": true,
"query": "let domain_lookBack= 14d;\nlet timeframe = 1d;\nlet top_million_list = Cisco_Umbrella\n| where EventType == \"proxylogs\"\n| where TimeGenerated > ago(domain_lookBack) and TimeGenerated < ago(timeframe)\n| extend Hostname = parse_url(UrlOriginal)[\"Host\"]\n| summarize count() by tostring(Hostname)\n| top 1000000 by count_\n| summarize make_list(Hostname);\nCisco_Umbrella\n| where EventType == \"proxylogs\"\n| where TimeGenerated > ago(timeframe)\n| extend Hostname = parse_url(UrlOriginal)[\"Host\"]\n| where Hostname !in (top_million_list)\n| extend Message = \"Connect to unpopular website (possible malicious payload delivery)\"\n| project Message, SrcIpAddr, DstIpAddr,UrlOriginal, TimeGenerated\n| extend IPCustomEntity = SrcIpAddr, UrlCustomEntity = UrlOriginal\n",
"queryFrequency": "P1D",
"queryPeriod": "P14D",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0,
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"CommandAndControl"
],
"alertRuleTemplateName": "75297f62-10a8-4fc1-9b2a-12f25c6f05a7",
"customDetails": null,
"entityMappings": [
{
"entityType": "URL",
"fieldMappings": [
{
"identifier": "Url",
"columnName": "UrlCustomEntity"
}
]
},
{
"entityType": "IP",
"fieldMappings": [
{
"identifier": "Address",
"columnName": "IPCustomEntity"
}
]
}
],
"templateVersion": "1.1.1",
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/CiscoUmbrella/CiscoUmbrellaConnectionToUnpopularWebsiteDetected.yaml"
}
}
]
}