Multiple integer overflows in X.org libX11 1.5.99.901 (1.6 RC1) and earlier allow X servers to trigger allocation of insufficient memory and a buffer overflow via vectors related to the (1) XQueryFont (2) _XF86BigfontQueryFont (3) XListFontsWithInfo (4) XGetMotionEvents (5) XListHosts (6) XGetModifierMapping (7) XGetPointerMapping (8) XGetKeyboardMapping (9) XGetWindowProperty (10) XGetImage (11) LoadColornameDB (12) XrmGetFileDatabase (13) _XimParseStringFile or (14) TransFileName functions.