BlackBerry maker RIM has warned users that opening certain malicious attachments on there push e-mail devices could stop them opening legitimate ones.
RIM has admitted that a software flaw in its BlackBerry Enterprise Server system, used to relay messages to BlackBerry mobile devices from corporate e-mail systems, allows specially crafted TIFF (Tagged Image File Format) files to attack mobile users.
If a user opens such an image it will block all subsequent attempts to open other types of attachments.
Other services, such as making voice calls, browsing the internet and sending and receiving e-mails, are not affected.
RIM says it has developed a fix to the problem but has not yet completed testing so the patch is so far unavailable.
In the meantime, RIM suggests that companies should filter out TIFF images from being sent to BlackBerry users or else stop all attachments being sent out.