https://blackwinghq.com/tags/fuzzing/Blackwing Intelligence provides high-end security engineering, analysis, and research services for engineering focused organizationsenSat, 22 Jun 2013 00:00:00 +0000https://blackwinghq.com/research/talks/xnu-spelunking/Sat, 22 Jun 2013 00:00:00 +0000https://blackwinghq.com/research/talks/xnu-spelunking/XNU, the OS X kernel, is made up of a somewhat unholy marriage of the monolithic BSD kernel and the CMU mach microkernel. Because of this marriage, in addition to BSD syscalls, XNU provides additional system calls and a large IPC interface for userland processes to interact with the underlying mach subsystem. The presence of these IPC interfaces significantly increases the available attack surface between the kernel and userland processes over just the traditional BSD system calls. This talk explores these interfaces and details the processes devised and lessons learned from building fuzzers for bug hunting in mach territory.