Red Hat Security Advisory: xorg-x11-server-Xwayland security update
Severity: highType: VulnerabilityCVE-2026-55999
Xwayland is an X server for running X clients under Wayland. Security Fix(es): * xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow (CVE-2026-55999) * X.org: xorg-x11-server: GLX contextTags Use-After-Free in CommonMakeCurrent() (CVE-2026-56000) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
EPSS 0.3%top 81%
Red Hat Security Advisory: xorg-x11-server-Xwayland security update
0
HighVulnerabilityCVE-2026-55999gcveosvubuntu-cve-2026-55999ubuntu-pro-14-04-ltsubuntu-pro-16-04-ltsubuntu-pro-18-04-ltsubuntu-pro-20-04-ltsubuntu-22-04-ltsubuntu-24-04-ltsubuntu-25-10ubuntu-26-04-ltscsafcve-2026-55999cve-2026-56000red-hat-product-security
Published: 07/13/2026 (07/13/2026, 06:57:37 UTC)
Source: GCVE Database
Vendor/Project: Red Hat Product Security
Product: Red Hat
Description
Xwayland is an X server for running X clients under Wayland. Security Fix(es): * xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow (CVE-2026-55999) * X.org: xorg-x11-server: GLX contextTags Use-After-Free in CommonMakeCurrent() (CVE-2026-56000) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Affected software
xorg-server
pkg:deb/ubuntu/xorg-server@2:1.15.1-0ubuntu2.11+esm12?arch=source&distro=esm-infra-legacy/trustyAffected versions
=2:1.14.3-3ubuntu2=2:1.14.3-3ubuntu3=2:1.14.3-3ubuntu4=2:1.14.3-5ubuntu1=2:1.14.4-1ubuntu1=2:1.14.4-1ubuntu2=2:1.14.4.901-0ubuntu2=2:1.14.5-1ubuntu2=2:1.14.5-1ubuntu4=2:1.15.0-1ubuntu1=2:1.15.0-1ubuntu2=2:1.15.0-1ubuntu3=2:1.15.0-1ubuntu4=2:1.15.0-1ubuntu6=2:1.15.0-1ubuntu7=2:1.15.1-0ubuntu1=2:1.15.1-0ubuntu2=2:1.15.1-0ubuntu2.1=2:1.15.1-0ubuntu2.4=2:1.15.1-0ubuntu2.5=2:1.15.1-0ubuntu2.6=2:1.15.1-0ubuntu2.7=2:1.15.1-0ubuntu2.9=2:1.15.1-0ubuntu2.10=2:1.15.1-0ubuntu2.11=2:1.15.1-0ubuntu2.11+esm2=2:1.15.1-0ubuntu2.11+esm3=2:1.15.1-0ubuntu2.11+esm4=2:1.15.1-0ubuntu2.11+esm5=2:1.15.1-0ubuntu2.11+esm6=2:1.15.1-0ubuntu2.11+esm7=2:1.15.1-0ubuntu2.11+esm8=2:1.15.1-0ubuntu2.11+esm9=2:1.15.1-0ubuntu2.11+esm11=2:1.15.1-0ubuntu2.11+esm12
xorg-server
pkg:deb/ubuntu/xorg-server@2:1.18.4-0ubuntu0.12+esm18?arch=source&distro=esm-infra/xenialAffected versions
=2:1.17.2-1ubuntu9=2:1.17.2-1ubuntu10=2:1.17.3-2ubuntu1=2:1.17.3-2ubuntu2=2:1.17.3-2ubuntu3=2:1.17.3-2ubuntu4=2:1.18.1-1ubuntu3=2:1.18.1-1ubuntu4=2:1.18.3-1ubuntu1=2:1.18.3-1ubuntu2=2:1.18.3-1ubuntu2.2=2:1.18.3-1ubuntu2.3=2:1.18.4-0ubuntu0.1=2:1.18.4-0ubuntu0.2=2:1.18.4-0ubuntu0.3=2:1.18.4-0ubuntu0.4=2:1.18.4-0ubuntu0.6=2:1.18.4-0ubuntu0.7=2:1.18.4-0ubuntu0.8=2:1.18.4-0ubuntu0.9=2:1.18.4-0ubuntu0.10=2:1.18.4-0ubuntu0.11=2:1.18.4-0ubuntu0.12=2:1.18.4-0ubuntu0.12+esm1=2:1.18.4-0ubuntu0.12+esm2=2:1.18.4-0ubuntu0.12+esm4=2:1.18.4-0ubuntu0.12+esm5=2:1.18.4-0ubuntu0.12+esm6=2:1.18.4-0ubuntu0.12+esm8=2:1.18.4-0ubuntu0.12+esm9=2:1.18.4-0ubuntu0.12+esm10=2:1.18.4-0ubuntu0.12+esm12=2:1.18.4-0ubuntu0.12+esm13=2:1.18.4-0ubuntu0.12+esm14=2:1.18.4-0ubuntu0.12+esm15=2:1.18.4-0ubuntu0.12+esm16=2:1.18.4-0ubuntu0.12+esm17=2:1.18.4-0ubuntu0.12+esm18
xorg-server-hwe-16.04
pkg:deb/ubuntu/xorg-server-hwe-16.04@2:1.19.6-1ubuntu4.1~16.04.6+esm10?arch=source&distro=esm-infra/xenialAffected versions
=2:1.18.4-1ubuntu6.1~16.04.1=2:1.18.4-1ubuntu6.1~16.04.2=2:1.19.3-1ubuntu1~16.04.2=2:1.19.3-1ubuntu1~16.04.3=2:1.19.3-1ubuntu1~16.04.4=2:1.19.5-0ubuntu2~16.04.1=2:1.19.6-1ubuntu4~16.04.1=2:1.19.6-1ubuntu4.1~16.04.1=2:1.19.6-1ubuntu4.1~16.04.2=2:1.19.6-1ubuntu4.1~16.04.3=2:1.19.6-1ubuntu4.1~16.04.4=2:1.19.6-1ubuntu4.1~16.04.5=2:1.19.6-1ubuntu4.1~16.04.6=2:1.19.6-1ubuntu4.1~16.04.6+esm1=2:1.19.6-1ubuntu4.1~16.04.6+esm3=2:1.19.6-1ubuntu4.1~16.04.6+esm4=2:1.19.6-1ubuntu4.1~16.04.6+esm5=2:1.19.6-1ubuntu4.1~16.04.6+esm6=2:1.19.6-1ubuntu4.1~16.04.6+esm7=2:1.19.6-1ubuntu4.1~16.04.6+esm8=2:1.19.6-1ubuntu4.1~16.04.6+esm9=2:1.19.6-1ubuntu4.1~16.04.6+esm10
xorg-server
pkg:deb/ubuntu/xorg-server@2:1.19.6-1ubuntu4.15+esm13?arch=source&distro=esm-infra/bionicAffected versions
=2:1.19.5-0ubuntu2=2:1.19.6-1ubuntu1=2:1.19.6-1ubuntu2=2:1.19.6-1ubuntu3=2:1.19.6-1ubuntu4=2:1.19.6-1ubuntu4.1=2:1.19.6-1ubuntu4.2=2:1.19.6-1ubuntu4.3=2:1.19.6-1ubuntu4.4=2:1.19.6-1ubuntu4.5=2:1.19.6-1ubuntu4.6=2:1.19.6-1ubuntu4.7=2:1.19.6-1ubuntu4.8=2:1.19.6-1ubuntu4.9=2:1.19.6-1ubuntu4.10=2:1.19.6-1ubuntu4.11=2:1.19.6-1ubuntu4.12=2:1.19.6-1ubuntu4.13=2:1.19.6-1ubuntu4.14=2:1.19.6-1ubuntu4.15=2:1.19.6-1ubuntu4.15+esm1=2:1.19.6-1ubuntu4.15+esm3=2:1.19.6-1ubuntu4.15+esm4=2:1.19.6-1ubuntu4.15+esm5=2:1.19.6-1ubuntu4.15+esm7=2:1.19.6-1ubuntu4.15+esm8=2:1.19.6-1ubuntu4.15+esm9=2:1.19.6-1ubuntu4.15+esm10=2:1.19.6-1ubuntu4.15+esm11=2:1.19.6-1ubuntu4.15+esm12=2:1.19.6-1ubuntu4.15+esm13
xorg-server-hwe-18.04
pkg:deb/ubuntu/xorg-server-hwe-18.04@2:1.20.8-2ubuntu2.2~18.04.11+esm5?arch=source&distro=esm-infra/bionicAffected versions
=2:1.20.1-3ubuntu2.1~18.04.1=2:1.20.4-1ubuntu3~18.04.1=2:1.20.5+git20191008-0ubuntu1~18.04.1=2:1.20.8-2ubuntu2.1~18.04.1=2:1.20.8-2ubuntu2.2~18.04.1=2:1.20.8-2ubuntu2.2~18.04.2=2:1.20.8-2ubuntu2.2~18.04.3=2:1.20.8-2ubuntu2.2~18.04.4=2:1.20.8-2ubuntu2.2~18.04.5=2:1.20.8-2ubuntu2.2~18.04.6=2:1.20.8-2ubuntu2.2~18.04.7=2:1.20.8-2ubuntu2.2~18.04.8=2:1.20.8-2ubuntu2.2~18.04.9=2:1.20.8-2ubuntu2.2~18.04.10=2:1.20.8-2ubuntu2.2~18.04.11=2:1.20.8-2ubuntu2.2~18.04.11+esm1=2:1.20.8-2ubuntu2.2~18.04.11+esm2=2:1.20.8-2ubuntu2.2~18.04.11+esm3=2:1.20.8-2ubuntu2.2~18.04.11+esm4=2:1.20.8-2ubuntu2.2~18.04.11+esm5
xorg-server
pkg:deb/ubuntu/xorg-server@2:1.20.13-1ubuntu1~20.04.20+esm1?arch=source&distro=esm-infra/focalAffected versions
=2:1.20.5+git20191008-0ubuntu1=2:1.20.6-1ubuntu1=2:1.20.7-2ubuntu1=2:1.20.7-2ubuntu2=2:1.20.8-2ubuntu2=2:1.20.8-2ubuntu2.1=2:1.20.8-2ubuntu2.2=2:1.20.8-2ubuntu2.3=2:1.20.8-2ubuntu2.4=2:1.20.8-2ubuntu2.6=2:1.20.9-2ubuntu1.1~20.04.1=2:1.20.9-2ubuntu1.2~20.04.1=2:1.20.9-2ubuntu1.2~20.04.2=2:1.20.11-1ubuntu1~20.04.2=2:1.20.13-1ubuntu1~20.04.2=2:1.20.13-1ubuntu1~20.04.3=2:1.20.13-1ubuntu1~20.04.4=2:1.20.13-1ubuntu1~20.04.5=2:1.20.13-1ubuntu1~20.04.6=2:1.20.13-1ubuntu1~20.04.8=2:1.20.13-1ubuntu1~20.04.9=2:1.20.13-1ubuntu1~20.04.12=2:1.20.13-1ubuntu1~20.04.14=2:1.20.13-1ubuntu1~20.04.15=2:1.20.13-1ubuntu1~20.04.16=2:1.20.13-1ubuntu1~20.04.17=2:1.20.13-1ubuntu1~20.04.18=2:1.20.13-1ubuntu1~20.04.19=2:1.20.13-1ubuntu1~20.04.20=2:1.20.13-1ubuntu1~20.04.20+esm1
xorg-server
pkg:deb/ubuntu/xorg-server@2:21.1.4-2ubuntu1.7~22.04.16?arch=source&distro=jammyAffected versions
=2:1.20.13-1ubuntu1=2:1.20.13-1ubuntu2=2:1.20.14-1ubuntu1=2:21.1.3-2ubuntu2=2:21.1.3-2ubuntu2.1=2:21.1.3-2ubuntu2.2=2:21.1.3-2ubuntu2.3=2:21.1.3-2ubuntu2.4=2:21.1.3-2ubuntu2.5=2:21.1.3-2ubuntu2.6=2:21.1.3-2ubuntu2.7=2:21.1.3-2ubuntu2.8=2:21.1.3-2ubuntu2.9=2:21.1.4-2ubuntu1.7~22.04.1=2:21.1.4-2ubuntu1.7~22.04.2=2:21.1.4-2ubuntu1.7~22.04.5=2:21.1.4-2ubuntu1.7~22.04.7=2:21.1.4-2ubuntu1.7~22.04.8=2:21.1.4-2ubuntu1.7~22.04.9=2:21.1.4-2ubuntu1.7~22.04.10=2:21.1.4-2ubuntu1.7~22.04.11=2:21.1.4-2ubuntu1.7~22.04.12=2:21.1.4-2ubuntu1.7~22.04.13=2:21.1.4-2ubuntu1.7~22.04.14=2:21.1.4-2ubuntu1.7~22.04.15=2:21.1.4-2ubuntu1.7~22.04.16
xwayland
pkg:deb/ubuntu/xwayland@2:22.1.1-1ubuntu0.20?arch=source&distro=jammyAffected versions
=2:21.1.2-0ubuntu1=2:21.1.3-1=2:21.1.3-1ubuntu1=2:21.1.4-1=2:22.1.0-1=2:22.1.1-1=2:22.1.1-1ubuntu0.1=2:22.1.1-1ubuntu0.2=2:22.1.1-1ubuntu0.3=2:22.1.1-1ubuntu0.4=2:22.1.1-1ubuntu0.5=2:22.1.1-1ubuntu0.6=2:22.1.1-1ubuntu0.7=2:22.1.1-1ubuntu0.9=2:22.1.1-1ubuntu0.10=2:22.1.1-1ubuntu0.11=2:22.1.1-1ubuntu0.12=2:22.1.1-1ubuntu0.13=2:22.1.1-1ubuntu0.14=2:22.1.1-1ubuntu0.15=2:22.1.1-1ubuntu0.17=2:22.1.1-1ubuntu0.18=2:22.1.1-1ubuntu0.19=2:22.1.1-1ubuntu0.20
xorg-server
pkg:deb/ubuntu/xorg-server@2:21.1.12-1ubuntu1.6?arch=source&distro=nobleAffected versions
=2:21.1.7-3ubuntu2=2:21.1.7-3ubuntu2.1=2:21.1.10-1ubuntu1=2:21.1.11-2ubuntu1=2:21.1.12-1ubuntu1=2:21.1.12-1ubuntu1.1=2:21.1.12-1ubuntu1.2=2:21.1.12-1ubuntu1.3=2:21.1.12-1ubuntu1.4=2:21.1.12-1ubuntu1.5=2:21.1.12-1ubuntu1.6
xwayland
pkg:deb/ubuntu/xwayland@2:23.2.6-1ubuntu0.8?arch=source&distro=nobleAffected versions
=2:23.2.0-1=2:23.2.0-1ubuntu0.1=2:23.2.3-1=2:23.2.4-1=2:23.2.4-1build1=2:23.2.4-1build2=2:23.2.4-1build3=2:23.2.6-1=2:23.2.6-1ubuntu0.1=2:23.2.6-1ubuntu0.2=2:23.2.6-1ubuntu0.4=2:23.2.6-1ubuntu0.5=2:23.2.6-1ubuntu0.6=2:23.2.6-1ubuntu0.7=2:23.2.6-1ubuntu0.8
xorg-server
pkg:deb/ubuntu/xorg-server@2:21.1.18-1ubuntu1.1?arch=source&distro=questingAffected versions
=2:21.1.16-1ubuntu1=2:21.1.18-1ubuntu1=2:21.1.18-1ubuntu1.1
xwayland
pkg:deb/ubuntu/xwayland@2:24.1.6-1ubuntu1.1?arch=source&distro=questingAffected versions
=2:24.1.6-1=2:24.1.6-1ubuntu1=2:24.1.6-1ubuntu1.1
xorg-server
pkg:deb/ubuntu/xorg-server@2:21.1.22-1ubuntu1?arch=source&distro=resoluteAffected versions
=2:21.1.18-1ubuntu1=2:21.1.21-1ubuntu1=2:21.1.22-1ubuntu1
xwayland
pkg:deb/ubuntu/xwayland@2:24.1.10-1?arch=source&distro=resoluteAffected versions
=2:24.1.6-1ubuntu1=2:24.1.8-1=2:24.1.9-1=2:24.1.10-1
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Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-55999
- Osv Schema Version
- 1.7.0
- Ecosystems
- ["Ubuntu:Pro:14.04:LTS","Ubuntu:Pro:16.04:LTS","Ubuntu:Pro:18.04:LTS","Ubuntu:Pro:20.04:LTS","Ubuntu:22.04:LTS","Ubuntu:24.04:LTS","Ubuntu:25.10","Ubuntu:26.04:LTS"]
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a58b47468715ace43d8d580
Added to database: 07/16/2026, 10:37:40 UTC
Last updated: 09/14/2026, 10:01:32 UTC
Views: 25
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External Links
NVD DatabaseMITRE CVEReference 1Reference 2Reference 3https://access.redhat.com/errata/RHSA-2026:38490https://access.redhat.com/security/updates/classification/#important24961652496193Canonical URLhttps://access.redhat.com/errata/RHSA-2026:50718Canonical URLhttps://access.redhat.com/errata/RHSA-2026:50100Canonical URLSearch on Google
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