Red Hat Security Advisory: xorg-x11-server security update
X.Org is an open-source implementation of the X Window System. It provides the basic low-level functionality that full-fledged graphical user interfaces are designed upon. 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.
AI Analysis
Technical Summary
This advisory covers three vulnerabilities in the X.Org X server's xwayland component: CVE-2026-33999 is an integer underflow in XKB compatibility map handling that can cause denial of service; CVE-2026-34001 is a use-after-free vulnerability leading to server crashes and possible memory corruption; CVE-2026-34003 involves out-of-bounds memory access causing information exposure and denial of service. These vulnerabilities affect multiple Red Hat Enterprise Linux 9 variants and related CodeReady Linux Builder products. Red Hat has released security updates to fix these issues as detailed in advisory RHSA-2026:11388.
Potential Impact
Successful exploitation of these vulnerabilities can result in denial of service conditions by crashing the X.Org X server or causing memory corruption. Additionally, one vulnerability allows information exposure through out-of-bounds memory access. These impacts can disrupt graphical user interface functionality on affected systems.
Mitigation Recommendations
Red Hat has released an official security update for xorg-x11-server addressing these vulnerabilities. Users of Red Hat Enterprise Linux 9 and related products should apply the update as described in Red Hat advisory RHSA-2026:11388 and the referenced article https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the vendor-provided patch.
Red Hat Security Advisory: xorg-x11-server security update
Description
X.Org is an open-source implementation of the X Window System. It provides the basic low-level functionality that full-fledged graphical user interfaces are designed upon. 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.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory covers three vulnerabilities in the X.Org X server's xwayland component: CVE-2026-33999 is an integer underflow in XKB compatibility map handling that can cause denial of service; CVE-2026-34001 is a use-after-free vulnerability leading to server crashes and possible memory corruption; CVE-2026-34003 involves out-of-bounds memory access causing information exposure and denial of service. These vulnerabilities affect multiple Red Hat Enterprise Linux 9 variants and related CodeReady Linux Builder products. Red Hat has released security updates to fix these issues as detailed in advisory RHSA-2026:11388.
Potential Impact
Successful exploitation of these vulnerabilities can result in denial of service conditions by crashing the X.Org X server or causing memory corruption. Additionally, one vulnerability allows information exposure through out-of-bounds memory access. These impacts can disrupt graphical user interface functionality on affected systems.
Mitigation Recommendations
Red Hat has released an official security update for xorg-x11-server addressing these vulnerabilities. Users of Red Hat Enterprise Linux 9 and related products should apply the update as described in Red Hat advisory RHSA-2026:11388 and the referenced article https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the vendor-provided patch.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:11388
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-34001","CVE-2026-34003"]
- Cvss Version
- null
Threat ID: 6a160980e29bf47b5064dbd4
Added to database: 05/26/2026, 20:58:40 UTC
Last enriched: 06/26/2026, 01:15:34 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 45
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