The GLX extension in XFree86 4.0 X.Org X Window System (aka X11 or X) X11R6.7 and X.Org Server (aka xserver and xorg-server) before 1.16.3 allows remote authenticated users to cause a denial of service (out-of-bounds read or write) or possibly execute arbitrary code via a crafted length or index value to the (1) __glXDisp_Render (2) __glXDisp_RenderLarge (3) __glXDispSwap_VendorPrivate (4) __glXDispSwap_VendorPrivateWithReply (5) set_client_info (6) __glXDispSwap_SetClientInfoARB (7) DoSwapInterval (8) DoGetProgramString (9) DoGetString (10) __glXDispSwap_RenderMode (11) __glXDisp_GetCompressedTexImage (12) __glXDispSwap_GetCompressedTexImage (13) __glXDisp_FeedbackBuffer (14) __glXDispSwap_FeedbackBuffer (15) __glXDisp_SelectBuffer (16) __glXDispSwap_SelectBuffer (17) __glXDisp_Flush (18) __glXDispSwap_Flush (19) __glXDisp_Finish (20) __glXDispSwap_Finish (21) __glXDisp_ReadPixels (22) __glXDispSwap_ReadPixels (23) __glXDisp_GetTexImage (24) __glXDispSwap_GetTexImage (25) __glXDisp_GetPolygonStipple (26) __glXDispSwap_GetPolygonStipple (27) __glXDisp_GetSeparableFilter (28) __glXDisp_GetSeparableFilterEXT (29) __glXDisp_GetConvolutionFilter (30) __glXDisp_GetConvolutionFilterEXT (31) __glXDisp_GetHistogram (32) __glXDisp_GetHistogramEXT (33) __glXDisp_GetMinmax (34) __glXDisp_GetMinmaxEXT (35) __glXDisp_GetColorTable (36) __glXDisp_GetColorTableSGI (37) GetSeparableFilter (38) GetConvolutionFilter (39) GetHistogram (40) GetMinmax or (41) GetColorTable function.