Logged In: YES 
user_id=11105

Scot, your patch is not correct because 'cmd' is never
executed.  However, I was able to reproduce the overwriting
of /dev/null by calling 'ctypes.util.find_library' for a
shared lib that does not exist.  Attached is a new patch
'util.diff' which fixes the problem for me.  Can you please
verify that it also works for you?

Thanks for finding the bug and locating the problem!