The ps_drv.sys kernel driver in ArcaBit ArcaVir 2009 Antivirus Protection 9.4.3201.9 and earlier, ArcaVir 2009 Internet Security 9.4.3202.9 and earlier, ArcaVir 2009 System Protection 9.4.3203.9 and earlier, and ArcaBit 2009 Home Protection 9.4.3204.9 and earlier, allows local users to gain privileges via crafted METHOD_NEITHER IOCTL requests to \Device\ps_drv containing arbitrary kernel addresses, as demonstrated using the (1) 0x2A7B802B and possibly (2) 0x2A7B8004 and (3) 0x2A7B802F IOCTLs.