CYFIRMA - Attack Surface - Open Ports High Rule

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Id	87e7eb3f-bb8e-46e5-8807-d3fc63d0f676
Rulename	CYFIRMA - Attack Surface - Open Ports High Rule
Description	“This rule is triggered when CYFIRMA identifies open and publicly accessible ports on internet-facing assets. Exposed services may include SSH, RDP, HTTP, or other potentially sensitive ports, increasing the risk of unauthorized access, exploitation, or reconnaissance by threat actors. Monitoring open ports is critical to reducing the external attack surface and preventing misuse through brute force, service vulnerabilities, or protocol exploitation.”
Severity	High
Tactics	InitialAccess CommandAndControl Discovery DefenseEvasion Persistence
Techniques	T1566 T1071 T1505
Required data connectors	CyfirmaAttackSurfaceAlertsConnector
Kind	Scheduled
Query frequency	5m
Query period	5m
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Cyfirma Attack Surface/Analytic Rules/ASOpenPortsHighRule.yaml
Version	1.0.1
Arm template	87e7eb3f-bb8e-46e5-8807-d3fc63d0f676.json

KQL

// High Severity - Open Ports Exposure Detected
let timeFrame = 5m;
CyfirmaASOpenPortsAlerts_CL
| where severity == 'Critical' and TimeGenerated between (ago(timeFrame) .. now())
| extend Description=description, FirstSeen=first_seen, LastSeen=last_seen, RiskScore=risk_score, Domain=sub_domain, TopDomain=top_domain, NetworkIP=ip, AlertUID=alert_uid, UID=uid, WebServer=web_server, WebServerVersion=web_server_version, OpenPorts=open_ports, ProviderName="CYFIRMA", ProductName="DeCYFIR/DeTCT"
| project
    TimeGenerated,
    Description,
    Domain,
    TopDomain,
    RiskScore,
    FirstSeen,
    LastSeen,
    NetworkIP,
    AlertUID,
    UID,
    WebServer,
    WebServerVersion,
    OpenPorts,
    ProductName,
    ProviderName

YAML

name: CYFIRMA - Attack Surface - Open Ports High Rule
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Cyfirma Attack Surface/Analytic Rules/ASOpenPortsHighRule.yaml
severity: High
description: |
    "This rule is triggered when CYFIRMA identifies open and publicly accessible ports on internet-facing assets. Exposed services may include SSH, RDP, HTTP, or other potentially sensitive ports, increasing the risk of unauthorized access, exploitation, or reconnaissance by threat actors. Monitoring open ports is critical to reducing the external attack surface and preventing misuse through brute force, service vulnerabilities, or protocol exploitation."
version: 1.0.1
customDetails:
  AlertUID: AlertUID
  FirstSeen: FirstSeen
  WebServer: WebServer
  UID: UID
  LastSeen: LastSeen
  OpenPorts: OpenPorts
  TimeGenerated: TimeGenerated
  WebServerVersion: WebServerVersion
  RiskScore: RiskScore
  Description: Description
requiredDataConnectors:
- dataTypes:
  - CyfirmaASOpenPortsAlerts_CL
  connectorId: CyfirmaAttackSurfaceAlertsConnector
tactics:
- InitialAccess
- CommandAndControl
- Discovery
- DefenseEvasion
- Persistence
relevantTechniques:
- T1566
- T1071
- T1505
kind: Scheduled
triggerThreshold: 0
status: Available
queryPeriod: 5m
incidentConfiguration:
  groupingConfiguration:
    reopenClosedIncident: false
    lookbackDuration: PT5H
    matchingMethod: AllEntities
    enabled: false
  createIncident: true
alertDetailsOverride:
  alertDescriptionFormat: CYFIRMA - High Severity Open Ports Exposure Detected on Assets - {{Description}}
  alertDisplayNameFormat: 'CYFIRMA - High Severity Open Ports Exposure Detected on Assets - Domain: {{Domain}}, IP: {{NetworkIP}}'
  alertDynamicProperties:
  - value: ProductName
    alertProperty: ProductName
  - value: ProviderName
    alertProperty: ProviderName
triggerOperator: gt
query: |
  // High Severity - Open Ports Exposure Detected
  let timeFrame = 5m;
  CyfirmaASOpenPortsAlerts_CL
  | where severity == 'Critical' and TimeGenerated between (ago(timeFrame) .. now())
  | extend Description=description, FirstSeen=first_seen, LastSeen=last_seen, RiskScore=risk_score, Domain=sub_domain, TopDomain=top_domain, NetworkIP=ip, AlertUID=alert_uid, UID=uid, WebServer=web_server, WebServerVersion=web_server_version, OpenPorts=open_ports, ProviderName="CYFIRMA", ProductName="DeCYFIR/DeTCT"
  | project
      TimeGenerated,
      Description,
      Domain,
      TopDomain,
      RiskScore,
      FirstSeen,
      LastSeen,
      NetworkIP,
      AlertUID,
      UID,
      WebServer,
      WebServerVersion,
      OpenPorts,
      ProductName,
      ProviderName  
eventGroupingSettings:
  aggregationKind: AlertPerResult
queryFrequency: 5m
entityMappings:
- entityType: DNS
  fieldMappings:
  - identifier: DomainName
    columnName: Domain
- entityType: Host
  fieldMappings:
  - identifier: HostName
    columnName: TopDomain
  - identifier: DnsDomain
    columnName: Domain
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: NetworkIP
id: 87e7eb3f-bb8e-46e5-8807-d3fc63d0f676

ARM