source: http://www.securityfocus.com/bid/26510/info

Apple Mac OS X is prone to a vulnerability that can allow arbitrary code to run. This issue affects the Mail application when handling email attachments.

Attackers can exploit this issue to execute arbitrary code in the context of the user running the application. This will compromise the application and possibly the underlying operating system.

This issue affects Mac OS X 10.5.

NOTE: This vulnerability may be related to CVE-2007-0395 documented in BID 16907 (Apple Mac OS X Security Update 2006-001 Multiple Vulnerabilities). Although the issues seem similar in nature, this may not be the very same underlying vulnerability. We will update this BID as more information emerges.

UPDATE (November 21, 2007): Reports indicate that this issue occurs because of an error in the application's quarantine feature. We have not confirmed this information.

UPDATE (December 17, 2007): This vulnerability stems from an unspecified implementation issue in the Launch Services application.
http://www.securityfocus.com/bid/16907 

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echo "heise Security: You are vulnerable."
echo
echo