SharePointFileOperation via devices with previously unseen user agents
Id | 5dd76a87-9f87-4576-bab3-268b0e2b338b |
Rulename | SharePointFileOperation via devices with previously unseen user agents |
Description | Identifies if the number of documents uploaded or downloaded from device(s) associated with a previously unseen user agent exceeds a threshold (default is 5). |
Severity | Medium |
Tactics | Exfiltration |
Techniques | T1030 |
Required data connectors | Office365 |
Kind | Scheduled |
Query frequency | 1d |
Query period | 8d |
Trigger threshold | 0 |
Trigger operator | gt |
Source Uri | https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft 365/Analytic Rules/SharePoint_Downloads_byNewUserAgent.yaml |
Version | 2.2.0 |
Arm template | 5dd76a87-9f87-4576-bab3-268b0e2b338b.json |
let threshold = 5;
let szSharePointFileOperation = "SharePointFileOperation";
let szOperations = dynamic(["FileDownloaded", "FileUploaded"]);
let starttime = 8d;
let endtime = 1d;
let historicalActivity =
OfficeActivity
| where TimeGenerated between(ago(starttime)..ago(endtime))
| where RecordType =~ szSharePointFileOperation
| where Operation in~ (szOperations)
| where isnotempty(UserAgent)
| summarize historicalCount = count() by UserAgent, RecordType, Operation;
let recentActivity = OfficeActivity
| where TimeGenerated > ago(endtime)
| where RecordType =~ szSharePointFileOperation
| where Operation in~ (szOperations)
| where isnotempty(UserAgent)
| summarize recentCount = count() by UserAgent, RecordType, Operation;
let RareUserAgent = recentActivity | join kind = leftanti (historicalActivity) on UserAgent
| order by recentCount desc, UserAgent
// More than 5 downloads/uploads from a new user agent today
| where recentCount > threshold;
OfficeActivity
| where TimeGenerated > ago(endtime)
| where RecordType =~ szSharePointFileOperation
| where Operation in~ (szOperations)
| where isnotempty(UserAgent)
| join kind= inner (RareUserAgent)
on UserAgent, RecordType, Operation
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), OfficeObjectIdCount = dcount(OfficeObjectId), OfficeObjectIdList = make_set(OfficeObjectId)
by RecordType, Operation, UserAgent, UserType, UserId, ClientIP, OfficeWorkload, Site_Url, UserAgentSeenCount = recentCount
| extend UserIdName = tostring(split(UserId, '@')[0]), UserIdUPNSuffix = tostring(split(UserId, '@')[1])
| project-reorder StartTime, EndTime, UserAgent, UserAgentSeenCount, UserId, ClientIP, Site_Url
| order by UserAgentSeenCount desc, UserAgent asc, UserId asc, Site_Url asc
queryPeriod: 8d
version: 2.2.0
relevantTechniques:
- T1030
queryFrequency: 1d
kind: Scheduled
name: SharePointFileOperation via devices with previously unseen user agents
id: 5dd76a87-9f87-4576-bab3-268b0e2b338b
entityMappings:
- fieldMappings:
- columnName: UserIdName
identifier: Name
- columnName: UserIdName
identifier: UPNSuffix
entityType: Account
- fieldMappings:
- columnName: ClientIP
identifier: Address
entityType: IP
- fieldMappings:
- columnName: Site_Url
identifier: Url
entityType: URL
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft 365/Analytic Rules/SharePoint_Downloads_byNewUserAgent.yaml
severity: Medium
query: |
let threshold = 5;
let szSharePointFileOperation = "SharePointFileOperation";
let szOperations = dynamic(["FileDownloaded", "FileUploaded"]);
let starttime = 8d;
let endtime = 1d;
let historicalActivity =
OfficeActivity
| where TimeGenerated between(ago(starttime)..ago(endtime))
| where RecordType =~ szSharePointFileOperation
| where Operation in~ (szOperations)
| where isnotempty(UserAgent)
| summarize historicalCount = count() by UserAgent, RecordType, Operation;
let recentActivity = OfficeActivity
| where TimeGenerated > ago(endtime)
| where RecordType =~ szSharePointFileOperation
| where Operation in~ (szOperations)
| where isnotempty(UserAgent)
| summarize recentCount = count() by UserAgent, RecordType, Operation;
let RareUserAgent = recentActivity | join kind = leftanti (historicalActivity) on UserAgent
| order by recentCount desc, UserAgent
// More than 5 downloads/uploads from a new user agent today
| where recentCount > threshold;
OfficeActivity
| where TimeGenerated > ago(endtime)
| where RecordType =~ szSharePointFileOperation
| where Operation in~ (szOperations)
| where isnotempty(UserAgent)
| join kind= inner (RareUserAgent)
on UserAgent, RecordType, Operation
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), OfficeObjectIdCount = dcount(OfficeObjectId), OfficeObjectIdList = make_set(OfficeObjectId)
by RecordType, Operation, UserAgent, UserType, UserId, ClientIP, OfficeWorkload, Site_Url, UserAgentSeenCount = recentCount
| extend UserIdName = tostring(split(UserId, '@')[0]), UserIdUPNSuffix = tostring(split(UserId, '@')[1])
| project-reorder StartTime, EndTime, UserAgent, UserAgentSeenCount, UserId, ClientIP, Site_Url
| order by UserAgentSeenCount desc, UserAgent asc, UserId asc, Site_Url asc
tactics:
- Exfiltration
description: |
'Identifies if the number of documents uploaded or downloaded from device(s) associated
with a previously unseen user agent exceeds a threshold (default is 5).'
requiredDataConnectors:
- connectorId: Office365
dataTypes:
- OfficeActivity
status: Available
triggerThreshold: 0
triggerOperator: gt
{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"workspace": {
"type": "String"
}
},
"resources": [
{
"id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/5dd76a87-9f87-4576-bab3-268b0e2b338b')]",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/5dd76a87-9f87-4576-bab3-268b0e2b338b')]",
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
"kind": "Scheduled",
"apiVersion": "2022-11-01",
"properties": {
"displayName": "SharePointFileOperation via devices with previously unseen user agents",
"description": "'Identifies if the number of documents uploaded or downloaded from device(s) associated\nwith a previously unseen user agent exceeds a threshold (default is 5).'\n",
"severity": "Medium",
"enabled": true,
"query": "let threshold = 5;\nlet szSharePointFileOperation = \"SharePointFileOperation\";\nlet szOperations = dynamic([\"FileDownloaded\", \"FileUploaded\"]);\nlet starttime = 8d;\nlet endtime = 1d;\nlet historicalActivity =\nOfficeActivity\n| where TimeGenerated between(ago(starttime)..ago(endtime))\n| where RecordType =~ szSharePointFileOperation\n| where Operation in~ (szOperations)\n| where isnotempty(UserAgent)\n| summarize historicalCount = count() by UserAgent, RecordType, Operation;\nlet recentActivity = OfficeActivity\n| where TimeGenerated > ago(endtime)\n| where RecordType =~ szSharePointFileOperation\n| where Operation in~ (szOperations)\n| where isnotempty(UserAgent)\n| summarize recentCount = count() by UserAgent, RecordType, Operation;\nlet RareUserAgent = recentActivity | join kind = leftanti (historicalActivity) on UserAgent\n| order by recentCount desc, UserAgent\n// More than 5 downloads/uploads from a new user agent today\n| where recentCount > threshold;\nOfficeActivity\n| where TimeGenerated > ago(endtime)\n| where RecordType =~ szSharePointFileOperation\n| where Operation in~ (szOperations)\n| where isnotempty(UserAgent)\n| join kind= inner (RareUserAgent)\non UserAgent, RecordType, Operation\n| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), OfficeObjectIdCount = dcount(OfficeObjectId), OfficeObjectIdList = make_set(OfficeObjectId) \nby RecordType, Operation, UserAgent, UserType, UserId, ClientIP, OfficeWorkload, Site_Url, UserAgentSeenCount = recentCount\n| extend UserIdName = tostring(split(UserId, '@')[0]), UserIdUPNSuffix = tostring(split(UserId, '@')[1])\n| project-reorder StartTime, EndTime, UserAgent, UserAgentSeenCount, UserId, ClientIP, Site_Url\n| order by UserAgentSeenCount desc, UserAgent asc, UserId asc, Site_Url asc\n",
"queryFrequency": "P1D",
"queryPeriod": "P8D",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0,
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"Exfiltration"
],
"techniques": [
"T1030"
],
"alertRuleTemplateName": "5dd76a87-9f87-4576-bab3-268b0e2b338b",
"customDetails": null,
"entityMappings": [
{
"fieldMappings": [
{
"identifier": "Name",
"columnName": "UserIdName"
},
{
"identifier": "UPNSuffix",
"columnName": "UserIdName"
}
],
"entityType": "Account"
},
{
"fieldMappings": [
{
"identifier": "Address",
"columnName": "ClientIP"
}
],
"entityType": "IP"
},
{
"fieldMappings": [
{
"identifier": "Url",
"columnName": "Site_Url"
}
],
"entityType": "URL"
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft 365/Analytic Rules/SharePoint_Downloads_byNewUserAgent.yaml",
"status": "Available",
"templateVersion": "2.2.0"
}
}
]
}