Office 365 Outlook doesn't show attachment with untrust authority

[cpan]

If a new email comes with attachment that has invalid digital signature or from untrusted certificate authority, a warning shows in the Outlook desktop, but the Office 365 Outlook flow would not detect the attachment in the step (when a new email arrives step). The "Has Attachment" shows 0. Is this behavior by design? Is it possible not to automatically filter out the attachment in the flow?