Detection rules › Kusto
SlackAudit - Multiple archived files uploaded in short period of time
'This query helps to detect when a user uploads multiple archived files in short period of time.'
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Exfiltration |
Rule body
id: 3db0cb83-5fa4-4310-a8a0-d8d66183f0bd
name: SlackAudit - Multiple archived files uploaded in short period of time
description: |
'This query helps to detect when a user uploads multiple archived files in short period of time.'
severity: Low
status: Available
requiredDataConnectors:
- connectorId: SlackAuditAPI
dataTypes:
- SlackAudit_CL
queryFrequency: 1d
queryPeriod: 1d
triggerOperator: gt
triggerThreshold: 0
tactics:
- Exfiltration
relevantTechniques:
- T1567
query: |
let threshold = 10;
SlackAudit
| where DvcAction =~ 'file_uploaded'
| extend FE = tolower(tostring(split(EntityFileName, '.')[-1]))
| where FE in~ ('tar', 'bz2', 'gz', 'tgz', 'z', 'tbz2', 'zst', 'zip', 'zipx', '7z', 'rar', 'sfx')
| summarize UploadCount = count(), StartTime = min(TimeGenerated), EndTime = max(TimeGenerated) by SrcUserName, bucket = bin(TimeGenerated, 15m)
| where UploadCount > threshold
| extend AccountCustomEntity = SrcUserName
entityMappings:
- entityType: Account
fieldMappings:
- identifier: FullName
columnName: AccountCustomEntity
version: 1.0.1
kind: Scheduled
Stages and Predicates
Parameters
let threshold = 10;
Stage 1: source
SlackAudit
Stage 2: where
| where DvcAction =~ 'file_uploaded'
Stage 3: extend
| extend FE = tolower(tostring(split(EntityFileName, '.')[-1]))
Stage 4: where
| where FE in~ ('tar', 'bz2', 'gz', 'tgz', 'z', 'tbz2', 'zst', 'zip', 'zipx', '7z', 'rar', 'sfx')
Stage 5: summarize
| summarize UploadCount = count(), StartTime = min(TimeGenerated), EndTime = max(TimeGenerated) by SrcUserName, bucket = bin(TimeGenerated, 15m)
Stage 6: where
| where UploadCount > threshold
Stage 7: extend
| extend AccountCustomEntity = SrcUserName
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
DvcAction | eq |
| field:"DvcAction" kind:eq value:"file_uploaded" |
FE | in |
| field:"FE" kind:in |
UploadCount | gt |
| field:"UploadCount" kind:gt value:"10" |
Output fields
These fields are emitted when the rule matches.
| Field | Source |
|---|---|
EndTime | summarize |
SrcUserName | summarize |
StartTime | summarize |
UploadCount | summarize |
bucket | summarize |
AccountCustomEntity | extend |