Ouch! That's bad...Where to start?
I can't imagine there are any actual "laws" against it - but there may be something in the data protection act -I havent checked into it but if it was me, I would "assume" that my application was confidential.
it's (unbelieveably!) unprofessionsal though Good luck with the application though.
No laws broken but just extremely unprofessional by the HR department.
No point in saying anything - just get on with it.
I would have expected your line manager to know that you were applying (but not every other goddam line manager).
Good luck.