Apple macOS 10.12.1 / iOS < 10.2 - syslogd Arbitrary Port Replacement

/ Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=977 syslogd running as root hosts the com.apple.system.logger mach service. It's part of the system.sb sandbox profile and so reachable from a lot of sandboxed contexts. Here's a snippet from its mach message handling loop...