BootCamp update with invalid signature ... ?

All-

Just downloaded the latest Wifi update for BootCamp on the Windows side of my MacBook. When I try to install, I get an error telling me that the driver has an invalid signature and the update cannot proceed. I am guessing that either (1) I am the victim of some fairly elaborate Windows malware, or (2) maybe Apple forgot to digitally sign their latest update? See the pic below. Anybody else have this problem?

_Bones_