While these attacks are not impossible on linux/bsd there are inherent weaknesses in design of Windows, Especially Windows XP/2003 that make these attacks more probable
Also due to the nature of Linux being a Monolithic Kernel and open source, there tends to be less issue with backward compatibility issues with Linux making it easier to update systems that today companies refuse to update windows on because it is not compatible with older hardware/software
Infact Linux often has the reverse problem in that hardware support for new technology often lags behind because hardware vendors focus on Windows first.
Also due to the nature of Linux being a Monolithic Kernel and open source, there tends to be less issue with backward compatibility issues with Linux making it easier to update systems that today companies refuse to update windows on because it is not compatible with older hardware/software
Infact Linux often has the reverse problem in that hardware support for new technology often lags behind because hardware vendors focus on Windows first.