The GLX extension in X.Org xserver 1.7.7 allows remote authenticated users to cause a denial of service (server crash) and possibly execute arbitrary code via (1) a crafted request that triggers a client swap in glx/glxcmdsswap.c; or (2) a crafted length or (3) a negative value in the screen field in a request to glx/glxcmds.c.
Exploitability
AV:NAC:MAu:SImpact
C:CI:CA:C8.5/AV:N/AC:M/Au:S/C:C/I:C/A:C