Software Engineering Institute

The BlackBerry Handheld web browser does not properly handle malformed JAD files. JAD files in J2ME are used to describe Java applications (icons, size, description, vendor, platform requirements, etc) to the BlackBerry Handheld. From RIM Technical Knowledge Center article KB-04755:

If the JAD file is formatted to contain a long application name and vendor string (i.e., 256 or more characters) to your BlackBerry device, the browser appears to stop responding.
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A browser dialog is not properly dismissed. The browser displays the application name or vendor string on the download screen (this appears as several lines). The long application name indicates that there may be problems with the JAD file and caution should be exercised when downloading the application.

By convincing a user to access a specially crafted JAD file, an unauthenticated, remote attacker could cause the browser to hang.

Upgrade

According to RIM Technical Knowledge Center article KB-04755: "Install BlackBerry Device Software 4.0.2 or later. To obtain the most recent version of the device software, contact your service provider."

Bypass browser dialog

To bypass the browser dialog, start a new browser application, or click on a URL from an email message.

Reset BlackBerry Handheld device

If necessary, reset the BlackBerry Handheld by removing and re-inserting the battery.