Corelight - Multiple files sent over HTTP with abnormal requests

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Id	7226d37b-50ee-4e3b-9f80-5b74080d8f2c
Rulename	Corelight - Multiple files sent over HTTP with abnormal requests
Description	Detects sources sending multiple compressed files greater than 10MBs sent over HTTP in a short amount of time.
Severity	Medium
Tactics	Exfiltration
Techniques	T1030
Required data connectors	Corelight
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/Corelight/Analytic Rules/CorelightMultipleFilesSentOverHTTPAbnormalRequests.yaml
Version	2.1.0
Arm template	7226d37b-50ee-4e3b-9f80-5b74080d8f2c.json

KQL

let threshold = 25;
let fl_size_threshold = 10000000;
corelight_http
| where method in~ ('POST', 'PUT')
| where isempty(referrer)
| where tolong(request_body_len) > fl_size_threshold
| summarize count() by uri, id_orig_h, bin(TimeGenerated, 15m)
| where count_ > threshold

YAML

name: Corelight - Multiple files sent over HTTP with abnormal requests
relevantTechniques:
- T1030
id: 7226d37b-50ee-4e3b-9f80-5b74080d8f2c
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Corelight/Analytic Rules/CorelightMultipleFilesSentOverHTTPAbnormalRequests.yaml
requiredDataConnectors:
- dataTypes:
  - Corelight_v2_http
  - corelight_http
  connectorId: Corelight
version: 2.1.0
severity: Medium
triggerThreshold: 0
queryPeriod: 1h
entityMappings:
- fieldMappings:
  - identifier: Address
    columnName: id_orig_h
  entityType: IP
queryFrequency: 1h
status: Available
query: |
  let threshold = 25;
  let fl_size_threshold = 10000000;
  corelight_http
  | where method in~ ('POST', 'PUT')
  | where isempty(referrer)
  | where tolong(request_body_len) > fl_size_threshold
  | summarize count() by uri, id_orig_h, bin(TimeGenerated, 15m)
  | where count_ > threshold  
tactics:
- Exfiltration
kind: Scheduled
description: |
    'Detects sources sending multiple compressed files greater than 10MBs sent over HTTP in a short amount of time.'
triggerOperator: gt

ARM