I have found in Perth that Recruiters will often put candidates forward for roles, without the candidates permission.
They will also tell candidates that they are recruiting for the role, thus stopping the candidate from applying direct, when the company has not actually placed the job with that agency.
My advice would be that if you can work out who the company is who is recruiting (from the agency ad, if it is genuine), then apply to the HR Department direct. You can always give them a call and ask them if they are advertising xxx job via xxx agency. If they are, you know the job is genuine but you will find the HR team would prefer you to email your CV to them directly.