xorg-x11-server before 1.19.5 was missing length validation in XFIXES extension allowing malicious X client to cause X server to crash or possibly execute arbitrary code.
Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:HI:HA:H9.8/CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HOther