The Component Object Model (COM) functions in PHP 5.x on Windows do not follow safe_mode and disable_functions restrictions, which allows context-dependent attackers to bypass intended limitations, as demonstrated by executing objects with the kill bit set in the corresponding ActiveX control Compatibility Flags, executing programs via a function in compatUI.dll, invoking wscript.shell via wscript.exe, invoking Scripting.FileSystemObject via wshom.ocx, and adding users via a function in shgina.dll, related to the com_load_typelib function.