Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Requires an authorized local/X11 client connection (AV:L, PR:L, AC:L); a read overrun leaks server memory (C:H) and crashes the server (A:H) but does not clearly enable writes (I:N).
Primary rating from Vendor (redhat).
CVSS VectorVendor: redhat
Lifecycle Timeline
4DescriptionCVE.org
A flaw was found in the X.Org X server. This integer underflow vulnerability, specifically in the XKB compatibility map handling, allows an attacker with local or remote X11 server access to trigger a buffer read overrun. This can lead to memory-safety violations and potentially a denial of service (DoS) or other severe impacts.
AnalysisAI
Memory-disclosure and denial-of-service in the X.Org X server arises from an integer underflow (CWE-191) in the XKB compatibility map handling, which lets a client with local or remote X11 access trigger an out-of-bounds buffer read. Any attacker able to open a connection to the display server can crash it or read adjacent server memory, with Red Hat and SUSE rating the technical impact as total; no public exploit identified at time of analysis and EPSS is negligible (0.01%, 2nd percentile). This was reported by Red Hat and affects the X server shipped across Red Hat Enterprise Linux 6 through 10.
Technical ContextAI
The X.Org Server is the reference implementation of the X11 display server that mediates between client applications and graphics/input hardware on most Linux and BSD desktops. The flaw lives in the XKB (X Keyboard Extension) subsystem, specifically the routines that parse and store compatibility maps (compat map) sent via XKB protocol requests. CWE-191 (integer underflow) indicates a size or count value is decremented below zero (or a subtraction wraps around on an unsigned type), producing a huge or invalid length that is then used as a bound for a read operation, causing the server to read past the end of an allocated buffer. Because a single X server process handles all connected clients with elevated access to input and framebuffer state, out-of-bounds reads in this code path can leak server-process memory to the malicious client or corrupt internal state enough to crash the server.
RemediationAI
Patch available per vendor advisory: apply the updated xorg-x11-server packages from your distribution and restart the X session (or reboot). Red Hat provides fixes via errata RHSA-2026:10739, RHSA-2026:11352, and RHSA-2026:11369 (https://access.redhat.com/errata/RHSA-2026:10739); SUSE publishes fixes in SUSE-SU-2026:1328 through 1335 and SUSE-SU-2026:21211 (https://www.suse.com/support/update/SUSE-SU-2026:1328/). Exact fixed package versions are enumerated in those errata and should be pulled directly rather than guessed. If patching must be deferred, reduce exposure by restricting who can connect to the display server: keep X access authorization enabled (never run 'xhost +'), disable remote TCP listening on the X server (the '-nolisten tcp' default) so only local authorized clients can reach it, and on multi-user hosts limit local login/console access - the trade-off is that legitimate remote X11 or multi-seat use cases will break. Migrating GUI workloads to Wayland where feasible removes this X-server code path entirely, at the cost of application compatibility testing.
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Same weakness CWE-191 – Integer Underflow
View allSame technique Denial Of Service
View allVendor StatusVendor
SUSE
Severity: High| Product | Status |
|---|---|
| Image SLES15-SP4-SAP Image SLES15-SP4-SAP-Azure Image SLES15-SP4-SAP-EC2 Image SLES15-SP4-SAP-GCE Image SLES15-SP4-SAPCAL Image SLES15-SP4-SAPCAL-Azure Image SLES15-SP4-SAPCAL-EC2 Image SLES15-SP4-SAPCAL-GCE | Affected |
| Image SLES15-SP5-SAPCAL-Azure Image SLES15-SP5-SAPCAL-GCE | Affected |
| Image SLES15-SP6-SAP Image SLES15-SP6-SAP-EC2 Image SLES15-SP6-SAPCAL Image SLES15-SP6-SAPCAL-EC2 | Affected |
| SUSE Liberty Linux 9 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP7 SUSE Linux Enterprise Server 15 SP7 SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | Fixed |
| SUSE Linux Enterprise Module for Development Tools 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 12 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Fixed |
| SUSE Linux Enterprise Server 16.0 SUSE Linux Enterprise Server for SAP applications 16.0 | Fixed |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP7 | Fixed |
| SUSE Manager Proxy LTS 4.3 | Fixed |
| SUSE Manager Retail Branch Server LTS 4.3 | Fixed |
| SUSE Manager Server LTS 4.3 | Fixed |
| openSUSE Leap 15.6 | Fixed |
| openSUSE Leap 16.0 | Fixed |
| openSUSE Tumbleweed | Fixed |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP7 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | Fixed |
| SUSE Linux Enterprise Module for Development Tools 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 16.0 | Fixed |
| SUSE Linux Enterprise Server 16.1 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Fixed |
| SUSE Linux Enterprise Server for SAP applications 16.1 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP7 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP7 | Fixed |
| openSUSE Leap 15.6 | Fixed |
| openSUSE Leap 15.6 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP4 | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP5 | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP6 | Fixed |
| SUSE Linux Enterprise Module for Development Tools 15 SP4 | Fixed |
| SUSE Linux Enterprise Module for Development Tools 15 SP5 | Fixed |
| SUSE Linux Enterprise Module for Development Tools 15 SP6 | Fixed |
| SUSE Linux Enterprise Server 12 SP5 | Fixed |
| SUSE Linux Enterprise Server 12 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security | Fixed |
| SUSE Linux Enterprise Server 15 SP4 | Fixed |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP5 | Fixed |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP6 | Fixed |
| SUSE Linux Enterprise Server 15 SP6 | Fixed |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Fixed |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 12 SP5 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Fixed |
| SUSE Manager Proxy 4.3 | Fixed |
| SUSE Manager Proxy LTS 4.3 | Fixed |
| SUSE Manager Retail Branch Server 4.3 | Fixed |
| SUSE Manager Retail Branch Server LTS 4.3 | Fixed |
| SUSE Manager Server 4.3 | Fixed |
| SUSE Manager Server LTS 4.3 | Fixed |
| SUSE CaaS Platform 4.0 | Fixed |
| SUSE Enterprise Storage 6 | Fixed |
| SUSE Enterprise Storage 7 | Fixed |
| SUSE Enterprise Storage 7.1 | Fixed |
| SUSE Linux Enterprise Desktop 12 SP2 | Fixed |
| SUSE Linux Enterprise Desktop 12 SP3 | Fixed |
| SUSE Linux Enterprise Desktop 12 SP4 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP1 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP2 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP3 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP4 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP5 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP6 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP6 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP1 | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP2 | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP3 | Fixed |
| SUSE Linux Enterprise Module for Development Tools 15 SP1 | Fixed |
| SUSE Linux Enterprise Module for Development Tools 15 SP2 | Fixed |
| SUSE Linux Enterprise Module for Development Tools 15 SP3 | Fixed |
| SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT | Fixed |
| SUSE Linux Enterprise Real Time 15 SP2 | Fixed |
| SUSE Linux Enterprise Real Time 15 SP3 | Fixed |
| SUSE Linux Enterprise Real Time 15 SP4 | Fixed |
| SUSE Linux Enterprise Server 12 SP2 | Fixed |
| SUSE Linux Enterprise Server 12 SP2-BCL | Fixed |
| SUSE Linux Enterprise Server 12 SP2-ESPOS | Fixed |
| SUSE Linux Enterprise Server 12 SP2-LTSS | Fixed |
| SUSE Linux Enterprise Server 12 SP3 | Fixed |
| SUSE Linux Enterprise Server 12 SP3-BCL | Fixed |
| SUSE Linux Enterprise Server 12 SP3-ESPOS | Fixed |
| SUSE Linux Enterprise Server 12 SP3-LTSS | Fixed |
| SUSE Linux Enterprise Server 12 SP4 | Fixed |
| SUSE Linux Enterprise Server 12 SP4-ESPOS | Fixed |
| SUSE Linux Enterprise Server 12 SP4-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP1 | Fixed |
| SUSE Linux Enterprise Server 15 SP1-BCL | Fixed |
| SUSE Linux Enterprise Server 15 SP1-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP2 | Fixed |
| SUSE Linux Enterprise Server 15 SP2-BCL | Fixed |
| SUSE Linux Enterprise Server 15 SP2-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP3 | Fixed |
| SUSE Linux Enterprise Server 15 SP3-BCL | Fixed |
| SUSE Linux Enterprise Server 15 SP3-LTSS | Fixed |
| SUSE Linux Enterprise Server for Raspberry Pi 12 SP2 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 12 SP2 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 12 SP3 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 12 SP4 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Fixed |
| SUSE Linux Enterprise Software Development Kit 12 SP2 | Fixed |
| SUSE Linux Enterprise Software Development Kit 12 SP3 | Fixed |
| SUSE Linux Enterprise Software Development Kit 12 SP4 | Fixed |
| SUSE Linux Enterprise Software Development Kit 12 SP5 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP1 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP2 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP3 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP4 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP5 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP6 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP6 | Fixed |
| SUSE Manager Proxy 4.0 | Fixed |
| SUSE Manager Proxy 4.1 | Fixed |
| SUSE Manager Proxy 4.2 | Fixed |
| SUSE Manager Retail Branch Server 4.0 | Fixed |
| SUSE Manager Retail Branch Server 4.1 | Fixed |
| SUSE Manager Retail Branch Server 4.2 | Fixed |
| SUSE Manager Server 4.0 | Fixed |
| SUSE Manager Server 4.1 | Fixed |
| SUSE Manager Server 4.2 | Fixed |
| SUSE OpenStack Cloud 7 | Fixed |
| SUSE OpenStack Cloud 8 | Fixed |
| SUSE OpenStack Cloud 9 | Fixed |
| SUSE OpenStack Cloud Crowbar 8 | Fixed |
| SUSE OpenStack Cloud Crowbar 9 | Fixed |
| openSUSE Leap 15.3 | Fixed |
| openSUSE Leap 15.4 | Fixed |
| openSUSE Leap 15.5 | Fixed |
| SUSE Manager Proxy 4.3 LTS | Fixed |
| SUSE Manager Retail Branch Server 4.3 LTS | Fixed |
| SUSE Manager Server 4.3 LTS | Fixed |
| suse/kiosk/xorg:21 | Fixed |
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External POC / Exploit Code
Leaving vuln.today
EUVD-2026-25229
GHSA-g562-3mh5-27v6