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

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

ARM