Core Security Technologies Advisory – An integer signedness error has been found in the amd64_set_ldt() function in the FreeBSD kernel code (define d in the /sys/amd64/amd64/sys_machdep.c file), which implements the i386_set_ldt system call on the amd64 version of the OS. This integer signedness issue ultimately leads to a heap overflow in the kernel, allowing local unprivileged attackers to crash the system. FreeBSD 10.2 amd64 is affected.