Cisco WSA - Unexpected uploads

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Id	32c460ad-2d40-43e9-8ead-5cdd1d7a3163
Rulename	Cisco WSA - Unexpected uploads
Description	Detects unexpected file uploads.
Severity	High
Tactics	Exfiltration
Techniques	T1567
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/CiscoWSA/Analytic Rules/CiscoWSADataExfiltration.yaml
Version	1.0.3
Arm template	32c460ad-2d40-43e9-8ead-5cdd1d7a3163.json

KQL

let f_cnt_upload_threshold = 5;
let f_upload_size_threshold = 5000000;
CiscoWSAEvent
| where HttpRequestMethod in~ ('POST', 'PUT')
| where isnotempty(AmpFileName)
| where UrlCategory in~ ('IW_fts', 'IW_osb')
| where DstBytes > f_upload_size_threshold
| summarize count() by AmpFileName, SrcUserName, bin(TimeGenerated, 10m)
| where count_ >= f_cnt_upload_threshold
| extend AccountCustomEntity = SrcUserName

YAML

triggerThreshold: 0
queryFrequency: 1h
id: 32c460ad-2d40-43e9-8ead-5cdd1d7a3163
kind: Scheduled
description: |
    'Detects unexpected file uploads.'
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: Name
    columnName: AccountCustomEntity
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoWSA/Analytic Rules/CiscoWSADataExfiltration.yaml
queryPeriod: 1h
query: |
  let f_cnt_upload_threshold = 5;
  let f_upload_size_threshold = 5000000;
  CiscoWSAEvent
  | where HttpRequestMethod in~ ('POST', 'PUT')
  | where isnotempty(AmpFileName)
  | where UrlCategory in~ ('IW_fts', 'IW_osb')
  | where DstBytes > f_upload_size_threshold
  | summarize count() by AmpFileName, SrcUserName, bin(TimeGenerated, 10m)
  | where count_ >= f_cnt_upload_threshold
  | extend AccountCustomEntity = SrcUserName  
requiredDataConnectors:
- connectorId: SyslogAma
  datatypes:
  - Syslog
severity: High
name: Cisco WSA - Unexpected uploads
tactics:
- Exfiltration
version: 1.0.3
status: Available
triggerOperator: gt
relevantTechniques:
- T1567

ARM