DESlock+ 3.2.6 and earlier, when DLMFENC.sys 1.0.0.26 and DLMFDISK.sys 1.2.0.27 are present, allows local users to gain privileges via a certain DLMFENC_IOCTL request to \\.\DLKPFSD_Device that overwrites a pointer, aka the "ring0 link list zero SYSTEM" vulnerability.