Detection rules › Kusto
Digital Guardian - Exfiltration to online fileshare
'Detects exfiltration to online fileshare.'
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Exfiltration |
Rule body
id: f7b6ddef-c1e9-46f0-8539-dbba7fb8a5b8
name: Digital Guardian - Exfiltration to online fileshare
description: |
'Detects exfiltration to online fileshare.'
severity: High
status: Available
requiredDataConnectors:
- connectorId: SyslogAma
datatypes:
- Syslog
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
- Exfiltration
relevantTechniques:
- T1048
query: |
let threshold = 10;
DigitalGuardianDLPEvent
| where isnotempty(inspected_document)
| where http_url contains 'dropbox' or http_url contains 'mega.nz'
| summarize f = dcount(inspected_document) by SrcUserName, bin(TimeGenerated, 30m)
| where f >= threshold
| extend AccountCustomEntity = SrcUserName
entityMappings:
- entityType: Account
fieldMappings:
- identifier: Name
columnName: AccountCustomEntity
version: 1.0.2
kind: Scheduled
Stages and Predicates
Parameters
let threshold = 10;
Stage 1: source
DigitalGuardianDLPEvent
Stage 2: where
| where isnotempty(inspected_document)
Stage 3: where
| where http_url contains 'dropbox' or http_url contains 'mega.nz'
Stage 4: summarize
| summarize f = dcount(inspected_document) by SrcUserName, bin(TimeGenerated, 30m)
Stage 5: where
| where f >= threshold
Stage 6: extend
| extend AccountCustomEntity = SrcUserName
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
f | ge |
| field:"f" kind:ge value:"10" |
http_url | contains |
| field:"http_url" kind:contains |
inspected_document | is_not_null | field:"inspected_document" kind:is_not_null |
Output fields
These fields are emitted when the rule matches.
| Field | Source |
|---|---|
SrcUserName | summarize |
f | summarize |
AccountCustomEntity | extend |