Cloudflare - XSS probing pattern in request
Id | 4d9d00b9-31a6-49e4-88c1-9e68277053ac |
Rulename | Cloudflare - XSS probing pattern in request |
Description | Detects XSS probing patterns. |
Severity | Medium |
Tactics | InitialAccess |
Techniques | T1190 T1133 |
Required data connectors | CloudflareDataConnector |
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/Cloudflare/Analytic Rules/CloudflareXSSProbingPattern.yaml |
Version | 1.0.0 |
Arm template | 4d9d00b9-31a6-49e4-88c1-9e68277053ac.json |
let s_threshold = 3;
Cloudflare
| where HttpRequestMethod in~ ('POST', 'PUT')
| extend susp_ch = countof(ClientRequestURI, '%00')
| where ClientRequestURI matches regex @'(alert\()|(alert\%28)|(String\.fromCharCode\()|(expression\(alert)' or susp_ch > s_threshold
| extend IPCustomEntity = SrcIpAddr
| extend UrlCustomEntity = ClientRequestURI
status: Available
queryFrequency: 1h
description: |
'Detects XSS probing patterns.'
severity: Medium
version: 1.0.0
relevantTechniques:
- T1190
- T1133
name: Cloudflare - XSS probing pattern in request
triggerThreshold: 0
kind: Scheduled
query: |
let s_threshold = 3;
Cloudflare
| where HttpRequestMethod in~ ('POST', 'PUT')
| extend susp_ch = countof(ClientRequestURI, '%00')
| where ClientRequestURI matches regex @'(alert\()|(alert\%28)|(String\.fromCharCode\()|(expression\(alert)' or susp_ch > s_threshold
| extend IPCustomEntity = SrcIpAddr
| extend UrlCustomEntity = ClientRequestURI
triggerOperator: gt
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Cloudflare/Analytic Rules/CloudflareXSSProbingPattern.yaml
requiredDataConnectors:
- connectorId: CloudflareDataConnector
dataTypes:
- Cloudflare
tactics:
- InitialAccess
id: 4d9d00b9-31a6-49e4-88c1-9e68277053ac
queryPeriod: 1h
entityMappings:
- fieldMappings:
- columnName: IPCustomEntity
identifier: Address
entityType: IP
- fieldMappings:
- columnName: UrlCustomEntity
identifier: Url
entityType: URL
{
"$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/4d9d00b9-31a6-49e4-88c1-9e68277053ac')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/4d9d00b9-31a6-49e4-88c1-9e68277053ac')]",
"properties": {
"alertRuleTemplateName": "4d9d00b9-31a6-49e4-88c1-9e68277053ac",
"customDetails": null,
"description": "'Detects XSS probing patterns.'\n",
"displayName": "Cloudflare - XSS probing pattern in request",
"enabled": true,
"entityMappings": [
{
"entityType": "IP",
"fieldMappings": [
{
"columnName": "IPCustomEntity",
"identifier": "Address"
}
]
},
{
"entityType": "URL",
"fieldMappings": [
{
"columnName": "UrlCustomEntity",
"identifier": "Url"
}
]
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Cloudflare/Analytic Rules/CloudflareXSSProbingPattern.yaml",
"query": "let s_threshold = 3;\nCloudflare\n| where HttpRequestMethod in~ ('POST', 'PUT')\n| extend susp_ch = countof(ClientRequestURI, '%00')\n| where ClientRequestURI matches regex @'(alert\\()|(alert\\%28)|(String\\.fromCharCode\\()|(expression\\(alert)' or susp_ch > s_threshold\n| extend IPCustomEntity = SrcIpAddr\n| extend UrlCustomEntity = ClientRequestURI\n",
"queryFrequency": "PT1H",
"queryPeriod": "PT1H",
"severity": "Medium",
"status": "Available",
"subTechniques": [],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"InitialAccess"
],
"techniques": [
"T1133",
"T1190"
],
"templateVersion": "1.0.0",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}