The LHA.sys driver before 1.1.1811.2101 in LG Device Manager exposes functionality that allows low-privileged users to read and write arbitrary physical memory via specially crafted IOCTL requests and elevate system privileges. This occurs because the device object has an associated symbolic link and an open DACL.
In dnsmasq before 2.78, if the DNS packet size does not match the expected size, the size parameter in a memset call gets a negative value. As it is an unsigned value, memset ends up writing up to 0xffffffff zero's (0xffffffffffffffff in 64 bit platforms), making dnsmasq crash.