Filezilla's installer now includes malware... suggest boycott.
To be absolutely clear I have no reason to think Filezilla Portable has been directly effected.
That said, starting with 3.9.0.5 Filezilla claims that updates to the next version can not be done automatically and directs users to download the installer from sourceforge... the installer for which is laden with malware and scamware which attempts to trick users into installing it.