The Sandbox.sys driver in Outpost Firewall PRO 4.0, and possibly earlier versions, does not validate arguments to hooked SSDT functions, which allows local users to cause a denial of service (crash) via invalid arguments to the (1) NtAssignProcessToJobObject,, (2) NtCreateKey, (3) NtCreateThread, (4) NtDeleteFile, (5) NtLoadDriver, (6) NtOpenProcess, (7) NtProtectVirtualMemory, (8) NtReplaceKey, (9) NtTerminateProcess, (10) NtTerminateThread, (11) NtUnloadDriver, and (12) NtWriteVirtualMemory functions.