RHSA-2026:11656 - Security Advisory

Topic

An update for xorg-x11-server-Xwayland is now available for Red Hat Enterprise Linux 8.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

Xwayland is an X server for running X clients under Wayland.

Security Fix(es):

• xorg: xwayland: X.Org X server: Denial of Service via integer underflow in XKB compatibility map handling (CVE-2026-33999)
• xorg: xwayland: X.Org X server: Use-after-free vulnerability leads to server crash and potential memory corruption (CVE-2026-34001)
• xorg: xwayland: X.Org X server: Information exposure and denial of service via out-of-bounds memory access (CVE-2026-34003)

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.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 8 x86_64
• Red Hat Enterprise Linux for IBM z Systems 8 s390x
• Red Hat Enterprise Linux for Power, little endian 8 ppc64le
• Red Hat Enterprise Linux for ARM 64 8 aarch64
• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 8.10 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 8.10 aarch64
• Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 8.10 ppc64le
• Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 8.10 s390x

Fixes

• BZ - 2451106 - CVE-2026-33999 xorg: xwayland: X.Org X server: Denial of Service via integer underflow in XKB compatibility map handling
• BZ - 2451109 - CVE-2026-34001 xorg: xwayland: X.Org X server: Use-after-free vulnerability leads to server crash and potential memory corruption
• BZ - 2451113 - CVE-2026-34003 xorg: xwayland: X.Org X server: Information exposure and denial of service via out-of-bounds memory access

CVEs

• CVE-2026-33999
• CVE-2026-34001
• CVE-2026-34003

References

• https://access.redhat.com/security/updates/classification/#important