SilverFox Targets Japanese Manufacturer with 3-Driver BYOVD Chain and ValleyRAT

The Chinese cybercrime group known as Silver Fox has been observed using new drivers as part of bring your own vulnerable driver (BYOVD) attacks targeting a Japanese organization in the industrial manufacturing sector to ultimately deliver ValleyRAT (aka Winos 4.0) for persistent remote access.

“In this campaign, the group combines new vulnerable-driver abuse, newly observed abuse of legitimate