How to find File Origin Info through M365 Defender

Hi raj871280 ,

 

The DeviceFileEvents contains Timestamp , which record the Date and time when the event was recorded. Additionally the ActionType will provide us information based on FileCreated, FileDeleted, FileModified or FileRenamed. (More here https://docs.microsoft.com/microsoft-365/security/defender/advanced-hunting-devicefileevents-table?view=o365-worldwide&WT.mc_id=M365-MVP-4024516)

 

Based on that understanding, we can do following steps:
1. query DeviceFileEvents group by FileName, Timestamp => unmodified file, will only have 1 record
2. filter the record having only 1 count.

 

Typical query would like this (please test)

DeviceFileEvents
| summarize totalTransaction=count() by FileName,FileOritinUrl, Timestamp
| where totalTransaction = 1

 

Cheers,

 

Riwut