KQL Search

//Find devices in your environment that have never triggered an ASR rule, you can likely turn on ASR for these devices without causing issues for the users.

//Data connector required for this query - M365 Defender - Device* tables

//Microsoft Sentinel query
//First find devices that have triggered an Attack Surface Reduction rule, either block or in audit mode.
let asrdevices=
    DeviceEvents
    | where TimeGenerated > ago (30d)
    | where ActionType startswith "Asr"
    | distinct DeviceName;
//Find all devices and exclude those that have previously triggered a rule
DeviceInfo
| where TimeGenerated > ago (30d)
| where OSPlatform startswith "Windows"
| summarize arg_max(TimeGenerated, *) by DeviceName
| where DeviceName !in (asrdevices)
| project
    ['Time Last Seen']=TimeGenerated,
    DeviceId,
    DeviceName,
    OSPlatform,
    OSVersion,
    LoggedOnUsers

//Advanced Hunting query

//Data connector required for this query - Advanced Hunting license

//First find devices that have triggered an Attack Surface Reduction rule, either block or in audit mode.
let asrdevices=
    DeviceEvents
    | where Timestamp > ago (30d)
    | where ActionType startswith "Asr"
    | distinct DeviceName;
//Find all devices and exclude those that have previously triggered a rule
DeviceInfo
| where Timestamp > ago (30d)
| where OSPlatform startswith "Windows"
| summarize arg_max(Timestamp, *) by DeviceName
| where DeviceName  !in (asrdevices)
| project
    ['Time Last Seen']=Timestamp,
    DeviceId,
    DeviceName,
    OSPlatform,
    OSVersion,
    LoggedOnUsers