Red Hat Security Advisory: xorg-x11-server-Xwayland security update
Multiple security vulnerabilities have been identified in the Xwayland component of the X.Org X server used for running X clients under Wayland. These include denial of service via integer underflow, information disclosure and denial of service via out-of-bounds reads, use-after-free leading to potential memory corruption, and information exposure through out-of-bounds memory access. The vulnerabilities affect Red Hat Enterprise Linux 9.6 Extended Update Support and related variants across multiple architectures. Red Hat has issued an important security advisory with updates to address these issues.
AI Analysis
Technical Summary
This advisory covers five security vulnerabilities in xorg-x11-server-Xwayland, a component of the X.Org X server that enables X clients to run under Wayland. The vulnerabilities include: CVE-2026-33999, a denial of service caused by an integer underflow in XKB compatibility map handling; CVE-2026-34000, information disclosure and denial of service via out-of-bounds read in XKB geometry processing; CVE-2026-34001, a use-after-free vulnerability that can cause server crashes and potential memory corruption; CVE-2026-34002, information disclosure or denial of service via out-of-bounds read in XKB modifier map handling; and CVE-2026-34003, information exposure and denial of service through out-of-bounds memory access. These vulnerabilities impact Red Hat Enterprise Linux 9.6 Extended Update Support and related CodeReady Linux Builder and SAP Solutions variants on multiple CPU architectures including x86_64, s390x, ppc64le, and aarch64. Red Hat has released updated packages to remediate these issues as detailed in advisory RHSA-2026:20561.
Potential Impact
The vulnerabilities can lead to denial of service conditions causing the X server to crash or become unresponsive. Some issues also allow information disclosure through out-of-bounds memory reads. The use-after-free vulnerability may result in memory corruption, potentially affecting system stability or security. These impacts affect systems running the vulnerable versions of xorg-x11-server-Xwayland on Red Hat Enterprise Linux 9.6 Extended Update Support and related variants.
Mitigation Recommendations
Red Hat has released updated xorg-x11-server-Xwayland packages that address these vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:20561 and the referenced article https://access.redhat.com/articles/11258. The update is available for Red Hat Enterprise Linux 9.6 Extended Update Support and related variants across supported architectures. Applying this update is the recommended remediation. No additional mitigation steps are indicated by the vendor advisory.
Red Hat Security Advisory: xorg-x11-server-Xwayland security update
Description
Multiple security vulnerabilities have been identified in the Xwayland component of the X.Org X server used for running X clients under Wayland. These include denial of service via integer underflow, information disclosure and denial of service via out-of-bounds reads, use-after-free leading to potential memory corruption, and information exposure through out-of-bounds memory access. The vulnerabilities affect Red Hat Enterprise Linux 9.6 Extended Update Support and related variants across multiple architectures. Red Hat has issued an important security advisory with updates to address these issues.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory covers five security vulnerabilities in xorg-x11-server-Xwayland, a component of the X.Org X server that enables X clients to run under Wayland. The vulnerabilities include: CVE-2026-33999, a denial of service caused by an integer underflow in XKB compatibility map handling; CVE-2026-34000, information disclosure and denial of service via out-of-bounds read in XKB geometry processing; CVE-2026-34001, a use-after-free vulnerability that can cause server crashes and potential memory corruption; CVE-2026-34002, information disclosure or denial of service via out-of-bounds read in XKB modifier map handling; and CVE-2026-34003, information exposure and denial of service through out-of-bounds memory access. These vulnerabilities impact Red Hat Enterprise Linux 9.6 Extended Update Support and related CodeReady Linux Builder and SAP Solutions variants on multiple CPU architectures including x86_64, s390x, ppc64le, and aarch64. Red Hat has released updated packages to remediate these issues as detailed in advisory RHSA-2026:20561.
Potential Impact
The vulnerabilities can lead to denial of service conditions causing the X server to crash or become unresponsive. Some issues also allow information disclosure through out-of-bounds memory reads. The use-after-free vulnerability may result in memory corruption, potentially affecting system stability or security. These impacts affect systems running the vulnerable versions of xorg-x11-server-Xwayland on Red Hat Enterprise Linux 9.6 Extended Update Support and related variants.
Mitigation Recommendations
Red Hat has released updated xorg-x11-server-Xwayland packages that address these vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:20561 and the referenced article https://access.redhat.com/articles/11258. The update is available for Red Hat Enterprise Linux 9.6 Extended Update Support and related variants across supported architectures. Applying this update is the recommended remediation. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:20561
- Cve Count
- 5
- Additional Cves
- ["CVE-2026-34000","CVE-2026-34001","CVE-2026-34002","CVE-2026-34003"]
- Cvss Version
- null
Threat ID: 6a160980e29bf47b5064cbf9
Added to database: 05/26/2026, 20:58:40 UTC
Last enriched: 07/13/2026, 10:49:18 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 89
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.