Cisco WSA - Multiple attempts to download unwanted file

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Id	46b6c6fc-2c1a-4270-be10-9d444d83f027
Rulename	Cisco WSA - Multiple attempts to download unwanted file
Description	Detects when multiple attempts to download unwanted file occur.
Severity	Medium
Tactics	InitialAccess
Techniques	T1189
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/CiscoWSAMultipleUnwantedFileTypes.yaml
Version	1.0.2
Arm template	46b6c6fc-2c1a-4270-be10-9d444d83f027.json

KQL

let threshold = 2;
CiscoWSAEvent
| where DvcAction =~ 'BLOCK_ADMIN_FILE_TYPE'
| summarize i_src = makeset(SrcIpAddr) by UrlOriginal, bin(TimeGenerated, 15m)
| where array_length(i_src) >= threshold
| extend IPCustomEntity = i_src, UrlCustomEntity = UrlOriginal

YAML

description: |
    'Detects when multiple attempts to download unwanted file occur.'
version: 1.0.2
triggerThreshold: 0
tactics:
- InitialAccess
queryPeriod: 1h
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoWSA/Analytic Rules/CiscoWSAMultipleUnwantedFileTypes.yaml
triggerOperator: gt
status: Available
id: 46b6c6fc-2c1a-4270-be10-9d444d83f027
name: Cisco WSA - Multiple attempts to download unwanted file
queryFrequency: 1h
severity: Medium
kind: Scheduled
entityMappings:
- fieldMappings:
  - columnName: IPCustomEntity
    identifier: Address
  entityType: IP
- fieldMappings:
  - columnName: UrlCustomEntity
    identifier: Url
  entityType: URL
relevantTechniques:
- T1189
query: |
  let threshold = 2;
  CiscoWSAEvent
  | where DvcAction =~ 'BLOCK_ADMIN_FILE_TYPE'
  | summarize i_src = makeset(SrcIpAddr) by UrlOriginal, bin(TimeGenerated, 15m)
  | where array_length(i_src) >= threshold
  | extend IPCustomEntity = i_src, UrlCustomEntity = UrlOriginal  
requiredDataConnectors:
- datatypes:
  - Syslog
  connectorId: SyslogAma

ARM