iDefense Security Advisory 11.14.07 - Local exploitation of an access validation vulnerability in Apple Inc.'s Mac OS X could allow an attacker to execute arbitrary code with root privileges. When executing a setuid-root binary, the Mach kernel does not reset the current thread Mach port, or the current thread Mach Exception Port. By first creating and obtaining write access to a Mach port, and then executing a set-uid root binary, an attacker can write arbitrary data into the address space of the process running as root. This leads to arbitrary code execution in the privileged process.
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