RHSA-2026:50116HighCVSS 7.5

Red Hat Security Advisory: xorg-x11-server security update

Published
August 4, 2026
Last Modified
August 4, 2026

🔗 CVE IDs covered (1)

CVE-2026-55999 →

📋 Description

CVE-2026-55999 — xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow

🎯 Affected products43

  • Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • xorg-x11-server-0:1.20.11-19.el8_8.1.src as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-0:1.20.11-19.el8_8.1.src as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • xorg-x11-server-Xdmx-0:1.20.11-19.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xdmx-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xdmx-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • xorg-x11-server-Xdmx-debuginfo-0:1.20.11-19.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xdmx-debuginfo-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xdmx-debuginfo-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • xorg-x11-server-Xephyr-0:1.20.11-19.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xephyr-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xephyr-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • xorg-x11-server-Xephyr-debuginfo-0:1.20.11-19.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xephyr-debuginfo-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xephyr-debuginfo-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • xorg-x11-server-Xnest-0:1.20.11-19.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xnest-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xnest-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • xorg-x11-server-Xnest-debuginfo-0:1.20.11-19.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xnest-debuginfo-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xnest-debuginfo-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • xorg-x11-server-Xorg-0:1.20.11-19.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xorg-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xorg-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • xorg-x11-server-Xorg-debuginfo-0:1.20.11-19.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xorg-debuginfo-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xorg-debuginfo-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • xorg-x11-server-Xvfb-0:1.20.11-19.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • xorg-x11-server-Xvfb-0:1.20.11-19.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • +13 more not shown

✅ Remediation

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258

🔗 References (4)