[filesys/miniFilter/avscan]: app maybe bypass scans via file mapping and subsequent memory writes.

Author: pengyanhshaCreated Apr 20, 2026Updated Aug 25, 2026
Labelsrequest

Which is the area where the sample lives?

/filesys/miniFilter/avscan

Describe the issue

The application performs file memory mapping, closes the opened file handle, and conducts write operations on the mapped memory area.Since the IRP_MJ_WRITE event is triggered after IRP_MJ_CLEANUP,scanning can be bypassed and relevant content may not be detected.Why not scan upon receiving the IRP_MJ_CLOSE notification also?

Source: microsoft/Windows-driver-samples