The "Open 'safe' files after downloading" option in Safari on Apple Mac OS X allows remote user-assisted attackers to execute arbitrary commands by tricking a user into downloading a __MACOSX folder that contains metadata (resource fork) that invokes the Terminal, which automatically interprets the script using bash, as demonstrated using a ZIP file that contains a script with a safe file extension.
https://exchange.xforce.ibmcloud.com/vulnerabilities/24808
https://euvd.enisa.europa.eu/vulnerability/EUVD-2006-0853
http://www.vupen.com/english/advisories/2006/0671
http://www.us-cert.gov/cas/techalerts/TA06-062A.html
http://www.securityfocus.com/bid/16736
http://www.mathematik.uni-ulm.de/numerik/staff/lehn/macosx.html
http://www.heise.de/english/newsticker/news/69862
http://www.frsirt.com/exploits/20060222.safari_safefiles_exec.pm.php
http://securitytracker.com/id?1015652