Cisco SEG - Potential phishing link

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Id	2e5158e1-9fc2-40ff-a909-c701a13a0405
Rulename	Cisco SEG - Potential phishing link
Description	Detects mails with suspicious links.
Severity	Medium
Tactics	InitialAccess
Techniques	T1566
Required data connectors	CefAma
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/CiscoSEG/Analytic Rules/CiscoSEGPotentialLinkToMalwareDownload.yaml
Version	1.0.3
Arm template	2e5158e1-9fc2-40ff-a909-c701a13a0405.json

KQL

let dl_cat = dynamic(['Illegal Downloads']);
CiscoSEGEvent
| where NetworkDirection =~ 'Incoming'
| where tostring(AdditionalFields) has 'ESAURLDetails'
| extend link_cat = extract(@"'Category': '(.*?)'", 1, tostring(AdditionalFields))
| where link_cat in~ (dl_cat)
| extend AccountCustomEntity = DstUserName

YAML

version: 1.0.3
tactics:
- InitialAccess
relevantTechniques:
- T1566
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountCustomEntity
  entityType: Account
triggerThreshold: 0
name: Cisco SEG - Potential phishing link
queryFrequency: 1h
triggerOperator: gt
kind: Scheduled
description: |
    'Detects mails with suspicious links.'
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGPotentialLinkToMalwareDownload.yaml
requiredDataConnectors:
- dataTypes:
  - CommonSecurityLog
  connectorId: CefAma
severity: Medium
query: |
  let dl_cat = dynamic(['Illegal Downloads']);
  CiscoSEGEvent
  | where NetworkDirection =~ 'Incoming'
  | where tostring(AdditionalFields) has 'ESAURLDetails'
  | extend link_cat = extract(@"'Category': '(.*?)'", 1, tostring(AdditionalFields))
  | where link_cat in~ (dl_cat)
  | extend AccountCustomEntity = DstUserName  
queryPeriod: 1h
id: 2e5158e1-9fc2-40ff-a909-c701a13a0405
status: Available

ARM