Cisco SEG - Malicious attachment not blocked

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Id	236e872c-31d1-4b45-ac2a-fda3af465c97
Rulename	Cisco SEG - Malicious attachment not blocked
Description	Detects mails with malicious attachments which were not blocked.
Severity	High
Tactics	InitialAccess
Techniques	T1566
Required data connectors	CefAma
Kind	Scheduled
Query frequency	10m
Query period	10m
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGMaliciousAttachmentNotBlocked.yaml
Version	1.0.3
Arm template	236e872c-31d1-4b45-ac2a-fda3af465c97.json

KQL

CiscoSEGEvent
| where NetworkDirection =~ 'Incoming'
| where SimplifiedDeviceAction =~ 'DELIVERED'
| where tostring(AdditionalFields) has 'ESAAMPVerdict'
| extend amp_verdict = extract(@'ESAAMPVerdict":"(NOT_EVALUATED|CLEAN|FA_PENDING|UNKNOWN|SKIPPED|UNSCANNABLE|LOW_RISK|MALICIOUS)"', 1, tostring(AdditionalFields))
| where amp_verdict =~ 'MALICIOUS'
| extend AccountCustomEntity = DstUserName

YAML

description: |
    'Detects mails with malicious attachments which were not blocked.'
version: 1.0.3
triggerThreshold: 0
tactics:
- InitialAccess
queryPeriod: 10m
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoSEG/Analytic Rules/CiscoSEGMaliciousAttachmentNotBlocked.yaml
triggerOperator: gt
status: Available
id: 236e872c-31d1-4b45-ac2a-fda3af465c97
name: Cisco SEG - Malicious attachment not blocked
queryFrequency: 10m
severity: High
kind: Scheduled
entityMappings:
- fieldMappings:
  - columnName: AccountCustomEntity
    identifier: Name
  entityType: Account
relevantTechniques:
- T1566
query: |
  CiscoSEGEvent
  | where NetworkDirection =~ 'Incoming'
  | where SimplifiedDeviceAction =~ 'DELIVERED'
  | where tostring(AdditionalFields) has 'ESAAMPVerdict'
  | extend amp_verdict = extract(@'ESAAMPVerdict":"(NOT_EVALUATED|CLEAN|FA_PENDING|UNKNOWN|SKIPPED|UNSCANNABLE|LOW_RISK|MALICIOUS)"', 1, tostring(AdditionalFields))
  | where amp_verdict =~ 'MALICIOUS'
  | extend AccountCustomEntity = DstUserName  
requiredDataConnectors:
- dataTypes:
  - CommonSecurityLog
  connectorId: CefAma

ARM