File input focus stealing vulnerability — Mozilla

A user on the Sla.ckers.org forums named hong reported that a file upload control could be filled programmatically by switching page focus to the label before a file upload form control for selected keyboard events. An attacker could use this trick to steal files from the users’ computer if the attacker knew the full pathnames to the desired fileis and could create a pretext that would convince the user to type long enough to produce all the necessary characters.