Adobe has released Reader X which includes a broker system sandbox to handle various system task related to previewing PDF files. Sand-Boxing technology has been available for MacOSX via seatbelt (sandbox-exec) in conjunction with a ".sb" configuration file. Users and administrators have had the capability to control executing processes actions including what file systems, spawing processes,hooking and network activity available.
What makes this exciting is that Adobe has included a similar sandbox to the one found in Google Chrome and has the option turned on as a default. Within Reader X agents control the writing to volumes, network sockets, process spawing and hooking. This is not full proof, but is a good start. Using Preview.app is the best solution at this time for viewing PDF files on the MacOSX. Reader X is worth a look and in the next release may prove to be once again the best solution for working with PDF files.
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