10 秒钟 root 一台 Mac 是怎么回事，如何防范？
下面这篇文章的末尾说，只要开启 FileVault 就安全了。
> Often times, physical access to a machine means game over. While people like to think that OSX is immune to most security threats, even Apple computers can be susceptible to physical attacks. Mac OSX is capable of booting into single user mode by holding a special key combination (Command-S). From this point, an attacker has root access to the entire computer. Note that this is not a security exploit, but rather an intentionally designed feature. While of course the intruder needs to be physically present, this can become a huge security problem.