Multics is an early time sharing mainframe operating system. Its development work started in 1964. It was developed by MIT, GE, and Bell Labs. It was not a successful commercial product, but an astounding fact was that some of the security features of Multics was far ahead of many of the current day operating systems.
Long back a vulnerability analysis was done on Multics, which revealed some significant vulnerabilities. There has been a paper submitted on this analysis which may be treated as a security checklist for any open system developed these days. Most of the vulnerabilities mentioned in this paper are valid for many of the existing systems. The bottomline conclusion of this paper is that any system that requires frequent restructuring may need a verifiable security kernal since there are professional exploiters attacking subsequent versions of a system. Here is the link for that paper.
