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

alertDetailsOverride:
  alertDynamicProperties:
  - alertProperty: ProductName
    value: ProductName
  - alertProperty: ProviderName
    value: ProviderName
  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}}'
incidentConfiguration:
  createIncident: true
  groupingConfiguration:
    matchingMethod: AllEntities
    lookbackDuration: PT5H
    reopenClosedIncident: false
    enabled: false
requiredDataConnectors:
- dataTypes:
  - CyfirmaASOpenPortsAlerts_CL
  connectorId: CyfirmaAttackSurfaceAlertsConnector
relevantTechniques:
- T1566
- T1071
- T1505
triggerOperator: gt
version: 1.0.1
queryFrequency: 5m
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."
triggerThreshold: 0
entityMappings:
- fieldMappings:
  - columnName: Domain
    identifier: DomainName
  entityType: DNS
- fieldMappings:
  - columnName: TopDomain
    identifier: HostName
  - columnName: Domain
    identifier: DnsDomain
  entityType: Host
- fieldMappings:
  - columnName: NetworkIP
    identifier: Address
  entityType: IP
customDetails:
  Description: Description
  FirstSeen: FirstSeen
  AlertUID: AlertUID
  TimeGenerated: TimeGenerated
  OpenPorts: OpenPorts
  WebServerVersion: WebServerVersion
  UID: UID
  LastSeen: LastSeen
  WebServer: WebServer
  RiskScore: RiskScore
name: CYFIRMA - Attack Surface - Open Ports High Rule
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  
tactics:
- InitialAccess
- CommandAndControl
- Discovery
- DefenseEvasion
- Persistence
queryPeriod: 5m
kind: Scheduled
id: 87e7eb3f-bb8e-46e5-8807-d3fc63d0f676
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Cyfirma Attack Surface/Analytic Rules/ASOpenPortsHighRule.yaml
eventGroupingSettings:
  aggregationKind: AlertPerResult
status: Available

ARM