SlackAudit - Multiple archived files uploaded in short period of time

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Id	3db0cb83-5fa4-4310-a8a0-d8d66183f0bd
Rulename	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
Tactics	Exfiltration
Techniques	T1567
Required data connectors	SlackAuditAPI
Kind	Scheduled
Query frequency	1d
Query period	1d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/SlackAudit/Analytic Rules/SlackAuditMultipleArchivedFilesUploadedInShortTimePeriod.yaml
Version	1.0.0
Arm template	3db0cb83-5fa4-4310-a8a0-d8d66183f0bd.json

KQL

let threshold = 10;
SlackAudit
| where DvcAction =~ 'file_uploaded'
| extend FE = extract(@'.*\.(.*)$', 1, EntityFileName)
| where FE in~ ('tar', 'bz2', 'gz', 'tgz', 'Z', 'tbz2', 'zst', 'zip', 'zipx', '7z', 'rar', 'sfx')
| summarize count() by SrcUserName, bucket = bin(TimeGenerated, 15m)
| where count_ > threshold
| extend AccountCustomEntity = SrcUserName

YAML

kind: Scheduled
queryPeriod: 1d
description: |
    'This query helps to detect when a user uploads multiple archived files in short period of time.'
tactics:
- Exfiltration
id: 3db0cb83-5fa4-4310-a8a0-d8d66183f0bd
requiredDataConnectors:
- connectorId: SlackAuditAPI
  dataTypes:
  - SlackAudit_CL
relevantTechniques:
- T1567
severity: Low
version: 1.0.0
status: Available
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: FullName
    columnName: AccountCustomEntity
name: SlackAudit - Multiple archived files uploaded in short period of time
triggerOperator: gt
query: |
  let threshold = 10;
  SlackAudit
  | where DvcAction =~ 'file_uploaded'
  | extend FE = extract(@'.*\.(.*)$', 1, EntityFileName)
  | where FE in~ ('tar', 'bz2', 'gz', 'tgz', 'Z', 'tbz2', 'zst', 'zip', 'zipx', '7z', 'rar', 'sfx')
  | summarize count() by SrcUserName, bucket = bin(TimeGenerated, 15m)
  | where count_ > threshold
  | extend AccountCustomEntity = SrcUserName  
queryFrequency: 1d
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/SlackAudit/Analytic Rules/SlackAuditMultipleArchivedFilesUploadedInShortTimePeriod.yaml
triggerThreshold: 0

ARM

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/3db0cb83-5fa4-4310-a8a0-d8d66183f0bd')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/3db0cb83-5fa4-4310-a8a0-d8d66183f0bd')]",
      "properties": {
        "alertRuleTemplateName": "3db0cb83-5fa4-4310-a8a0-d8d66183f0bd",
        "customDetails": null,
        "description": "'This query helps to detect when a user uploads multiple archived files in short period of time.'\n",
        "displayName": "SlackAudit - Multiple archived files uploaded in short period of time",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "AccountCustomEntity",
                "identifier": "FullName"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/SlackAudit/Analytic Rules/SlackAuditMultipleArchivedFilesUploadedInShortTimePeriod.yaml",
        "query": "let threshold = 10;\nSlackAudit\n| where DvcAction =~ 'file_uploaded'\n| extend FE = extract(@'.*\\.(.*)$', 1, EntityFileName)\n| where FE in~ ('tar', 'bz2', 'gz', 'tgz', 'Z', 'tbz2', 'zst', 'zip', 'zipx', '7z', 'rar', 'sfx')\n| summarize count() by SrcUserName, bucket = bin(TimeGenerated, 15m)\n| where count_ > threshold\n| extend AccountCustomEntity = SrcUserName\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Low",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Exfiltration"
        ],
        "techniques": [
          "T1567"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}