The \Device\SymEvent driver in Symantec Norton Personal Firewall 2006 9.1.0.33, and other versions of Norton Personal Firewall, Internet Security, AntiVirus, SystemWorks, Symantec Client Security SCS 1.x, 2.x, 3.0, and 3.1, Symantec AntiVirus Corporate Edition SAVCE 8.x, 9.x, 10.0, and 10.1, Symantec pcAnywhere 11.5 only, and Symantec Host, allows local users to cause a denial of service (system crash) via invalid data, as demonstrated by calling DeviceIoControl to send the data.