Red Hat Security Advisory: xorg-x11-server-Xwayland security update
Affects Red Hat xorg-serverSource GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 7.8 High.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 23 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSxorg-serverpkg:deb/ubuntu/xorg-server?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSxwaylandpkg:deb/ubuntu/xwayland?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 25.10xorg-serverpkg:deb/ubuntu/xorg-server?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10xwaylandpkg:deb/ubuntu/xwayland?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSxorg-serverpkg:deb/ubuntu/xorg-server?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSxwaylandpkg:deb/ubuntu/xwayland?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has issued an important security update for xorg-x11-server-Xwayland in Red Hat Enterprise Linux 9.2 that addresses these vulnerabilities. Users should apply the update as detailed in Red Hat advisory RHSA-2026:20547 and the referenced article https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the official patch.
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) * xwayland: xorg: X.Org X server: Information disclosure and denial of service via out-of-bounds read in XKB geometry processing. (CVE-2026-34000) * 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 disclosure or Denial of Service via out-of-bounds read in XKB modifier map handling (CVE-2026-34002) * 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.
References
- access.redhat.com/errata/RHSA-2026:20547 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2451106 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2451107 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2451109 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2451112 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2451113 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_20547.json (opens in a new tab)
- suse.com/support/security/rating/ (opens in a new tab)
- ftp.suse.com/pub/projects/security/csaf/opensuse-su-2026_20560-1.json (opens in a new tab)
- bugzilla.suse.com/1260922 (opens in a new tab)
- bugzilla.suse.com/1260923 (opens in a new tab)
- bugzilla.suse.com/1260924 (opens in a new tab)
- bugzilla.suse.com/1260925 (opens in a new tab)
- bugzilla.suse.com/1260926 (opens in a new tab)
- suse.com/security/cve/CVE-2026-33999/ (opens in a new tab)
- suse.com/security/cve/CVE-2026-34000/ (opens in a new tab)
- suse.com/security/cve/CVE-2026-34001/ (opens in a new tab)
- suse.com/security/cve/CVE-2026-34002/ (opens in a new tab)
- suse.com/security/cve/CVE-2026-34003/ (opens in a new tab)
- ubuntu.com/security/CVE-2026-33999 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-33999 (opens in a new tab)
- lists.x.org/archives/xorg-announce/2026-April/003677.html (opens in a new tab)