Elastic Security Detection Rules

New ActiveSyncAllowedDeviceID Added via PowerShell

Last updated 2 months ago on 2025-03-20
Created 4 years ago on 2020-12-15

About

Identifies the use of the Exchange PowerShell cmdlet, Set-CASMailbox, to add a new ActiveSync allowed device. Adversaries may target user email to collect sensitive information.
Tags
Domain: EndpointOS: WindowsUse Case: Threat DetectionTactic: PersistenceTactic: ExecutionData Source: Elastic EndgameData Source: Elastic DefendData Source: Windows Security Event LogsData Source: Microsoft Defender for EndpointData Source: SysmonData Source: SentinelOneData Source: CrowdstrikeLanguage: eql
Severity
medium
Risk Score
47
MITRE ATT&CK™

Persistence (TA0003)(opens in a new tab or window)

↳ Account Manipulation (T1098)(opens in a new tab or window)

Execution (TA0002)(opens in a new tab or window)

↳ Command and Scripting Interpreter (T1059)(opens in a new tab or window)

False Positive Examples
Legitimate exchange system administration activity.
License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
Event Correlation Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
endgame-*logs-crowdstrike.fdr*logs-endpoint.events.process-*logs-m365_defender.event-*logs-sentinel_one_cloud_funnel.*logs-system.security*logs-windows.forwarded*logs-windows.sysmon_operational-*winlogbeat-*
Related Integrations

endpoint(opens in a new tab or window)

windows(opens in a new tab or window)

system(opens in a new tab or window)

m365_defender(opens in a new tab or window)

sentinel_one_cloud_funnel(opens in a new tab or window)

crowdstrike(opens in a new tab or window)

Query
process where host.os.type == "windows" and event.type == "start" and
  process.name: ("powershell.exe", "pwsh.exe", "powershell_ise.exe") and process.args : "Set-CASMailbox*ActiveSyncAllowedDeviceIDs*"

Install detection rules in Elastic Security

Detect New ActiveSyncAllowedDeviceID Added via PowerShell in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).