Rare subscription-level operations in Azure

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Id	23de46ea-c425-4a77-b456-511ae4855d69
Rulename	Rare subscription-level operations in Azure
Description	This query looks for a few sensitive subscription-level events based on Azure Activity Logs. For example, this monitors for the operation name ‘Create or Update Snapshot’, which is used for creating backups but could be misused by attackers to dump hashes or extract sensitive information from the disk.
Severity	Low
Tactics	CredentialAccess Persistence
Techniques	T1003 T1098
Required data connectors	AzureActivity
Kind	Scheduled
Query frequency	1d
Query period	14d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/RareOperations.yaml
Version	2.0.3
Arm template	23de46ea-c425-4a77-b456-511ae4855d69.json

KQL

let starttime = 14d;
let endtime = 1d;
// The number of operations above which an IP address is considered an unusual source of role assignment operations
let alertOperationThreshold = 5;
// Add or remove operation names below as per your requirements. For operations lists, please refer to https://learn.microsoft.com/en-us/Azure/role-based-access-control/resource-provider-operations#all
let SensitiveOperationList =  dynamic(["microsoft.compute/snapshots/write", "microsoft.network/networksecuritygroups/write", "microsoft.storage/storageaccounts/listkeys/action"]);
let SensitiveActivity = AzureActivity
| where OperationNameValue in~ (SensitiveOperationList) or OperationNameValue hassuffix "listkeys/action"
| where ActivityStatusValue =~ "Success";
SensitiveActivity
| where TimeGenerated between (ago(starttime) .. ago(endtime))
| summarize count() by CallerIpAddress, Caller, OperationNameValue, bin(TimeGenerated,1d)
| where count_ >= alertOperationThreshold
// Returns all the records from the right side that don't have matches from the left
| join kind = rightanti (
SensitiveActivity
| where TimeGenerated >= ago(endtime)
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), ActivityTimeStamp = make_list(TimeGenerated), ActivityStatusValue = make_list(ActivityStatusValue), CorrelationIds = make_list(CorrelationId), ResourceGroups = make_list(ResourceGroup), ResourceIds = make_list(_ResourceId), ActivityCountByCallerIPAddress = count()
by CallerIpAddress, Caller, OperationNameValue
| where ActivityCountByCallerIPAddress >= alertOperationThreshold
) on CallerIpAddress, Caller, OperationNameValue
| extend Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])

YAML

entityMappings:
- fieldMappings:
  - columnName: Caller
    identifier: FullName
  - columnName: Name
    identifier: Name
  - columnName: UPNSuffix
    identifier: UPNSuffix
  entityType: Account
- fieldMappings:
  - columnName: CallerIpAddress
    identifier: Address
  entityType: IP
triggerOperator: gt
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/RareOperations.yaml
version: 2.0.3
tactics:
- CredentialAccess
- Persistence
queryPeriod: 14d
kind: Scheduled
id: 23de46ea-c425-4a77-b456-511ae4855d69
severity: Low
query: |
  let starttime = 14d;
  let endtime = 1d;
  // The number of operations above which an IP address is considered an unusual source of role assignment operations
  let alertOperationThreshold = 5;
  // Add or remove operation names below as per your requirements. For operations lists, please refer to https://learn.microsoft.com/en-us/Azure/role-based-access-control/resource-provider-operations#all
  let SensitiveOperationList =  dynamic(["microsoft.compute/snapshots/write", "microsoft.network/networksecuritygroups/write", "microsoft.storage/storageaccounts/listkeys/action"]);
  let SensitiveActivity = AzureActivity
  | where OperationNameValue in~ (SensitiveOperationList) or OperationNameValue hassuffix "listkeys/action"
  | where ActivityStatusValue =~ "Success";
  SensitiveActivity
  | where TimeGenerated between (ago(starttime) .. ago(endtime))
  | summarize count() by CallerIpAddress, Caller, OperationNameValue, bin(TimeGenerated,1d)
  | where count_ >= alertOperationThreshold
  // Returns all the records from the right side that don't have matches from the left
  | join kind = rightanti (
  SensitiveActivity
  | where TimeGenerated >= ago(endtime)
  | summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), ActivityTimeStamp = make_list(TimeGenerated), ActivityStatusValue = make_list(ActivityStatusValue), CorrelationIds = make_list(CorrelationId), ResourceGroups = make_list(ResourceGroup), ResourceIds = make_list(_ResourceId), ActivityCountByCallerIPAddress = count()
  by CallerIpAddress, Caller, OperationNameValue
  | where ActivityCountByCallerIPAddress >= alertOperationThreshold
  ) on CallerIpAddress, Caller, OperationNameValue
  | extend Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])  
triggerThreshold: 0
name: Rare subscription-level operations in Azure
status: Available
description: |
    'This query looks for a few sensitive subscription-level events based on Azure Activity Logs. For example, this monitors for the operation name 'Create or Update Snapshot', which is used for creating backups but could be misused by attackers to dump hashes or extract sensitive information from the disk.'
relevantTechniques:
- T1003
- T1098
requiredDataConnectors:
- connectorId: AzureActivity
  dataTypes:
  - AzureActivity
queryFrequency: 1d

ARM