Port Scan Detected

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Id	427e4c9e-8cf4-4094-a684-a2d060dbca38
Rulename	Port Scan Detected
Description	This alert creates an incident when a source IP addresses attempt to communicate with a large amount of distinct ports within a short period.
Severity	Medium
Tactics	Discovery
Techniques	T1046
Required data connectors	SyslogAma
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/Sophos XG Firewall/Analytic Rules/PortScanDetected.yaml
Version	1.0.4
Arm template	427e4c9e-8cf4-4094-a684-a2d060dbca38.json

KQL

let threshold = 50;
SophosXGFirewall
| where Log_Type =~ "Firewall"
| where not(ipv4_is_match("10.0.0.0",Src_IP,8) or ipv4_is_match("172.16.0.0",Src_IP,12) or ipv4_is_match("192.168.0.0",Src_IP,16))
| summarize dcount(Dst_Port) by Src_IP, bin(TimeGenerated, 5m)
| where dcount_Dst_Port > threshold

YAML

triggerThreshold: 0
entityMappings:
- fieldMappings:
  - identifier: Address
    columnName: Src_IP
  entityType: IP
tactics:
- Discovery
version: 1.0.4
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Sophos XG Firewall/Analytic Rules/PortScanDetected.yaml
queryPeriod: 1h
kind: Scheduled
relevantTechniques:
- T1046
name: Port Scan Detected
id: 427e4c9e-8cf4-4094-a684-a2d060dbca38
status: Available
description: |
    'This alert creates an incident when a source IP addresses attempt to communicate with a large amount of distinct ports within a short period.'
severity: Medium
queryFrequency: 1h
requiredDataConnectors:
- connectorId: SyslogAma
  datatypes:
  - Syslog
query: |
  let threshold = 50;
  SophosXGFirewall
  | where Log_Type =~ "Firewall"
  | where not(ipv4_is_match("10.0.0.0",Src_IP,8) or ipv4_is_match("172.16.0.0",Src_IP,12) or ipv4_is_match("192.168.0.0",Src_IP,16))
  | summarize dcount(Dst_Port) by Src_IP, bin(TimeGenerated, 5m)
  | where dcount_Dst_Port > threshold  
triggerOperator: gt

ARM