Cisco WSA - Unexpected file type

Back


Id	8e9d1f70-d529-4598-9d3e-5dd5164d1d02
Rulename	Cisco WSA - Unexpected file type
Description	Detects unexpected file type.
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/CiscoWSAUnexpectedFileType.yaml
Version	1.0.2
Arm template	8e9d1f70-d529-4598-9d3e-5dd5164d1d02.json

KQL

CiscoWSAEvent
| where isnotempty(AmpFileName)
| where isempty(AmpThreatName)
| where ResponseBodyMimeType =~ 'application/octet-stream'
| where AmpFileName !endswith '.exe'
| extend IPCustomEntity = SrcIpAddr, AccountCustomEntity = SrcUserName

YAML

description: |
    'Detects unexpected file type.'
kind: Scheduled
tactics:
- InitialAccess
requiredDataConnectors:
- connectorId: SyslogAma
  datatypes:
  - Syslog
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoWSA/Analytic Rules/CiscoWSAUnexpectedFileType.yaml
severity: Medium
name: Cisco WSA - Unexpected file type
triggerThreshold: 0
queryPeriod: 1h
query: |
  CiscoWSAEvent
  | where isnotempty(AmpFileName)
  | where isempty(AmpThreatName)
  | where ResponseBodyMimeType =~ 'application/octet-stream'
  | where AmpFileName !endswith '.exe'
  | extend IPCustomEntity = SrcIpAddr, AccountCustomEntity = SrcUserName  
relevantTechniques:
- T1189
id: 8e9d1f70-d529-4598-9d3e-5dd5164d1d02
queryFrequency: 1h
status: Available
triggerOperator: gt
version: 1.0.2
entityMappings:
- entityType: IP
  fieldMappings:
  - columnName: IPCustomEntity
    identifier: Address
- entityType: Account
  fieldMappings:
  - columnName: AccountCustomEntity
    identifier: Name

ARM