## Summary
CVE-2026-34003 is a local memory-safety flaw in the X.Org X server’s XKB key types request validation. A specially crafted request can trigger an out-of-bounds memory access, potentially leading to sensitive information disclosure or a crash (DoS).
## Technical Details
- Affected component: X.Org X server XKB key types request validation.
- Vulnerability class: CWE-125 (out-of-bounds read/write).
- Attack vector: LOCAL with PR:L (local attacker can send crafted requests to the X server).
- Likely outcomes:
- Out-of-bounds memory access causing sensitive information disclosure.
- Out-of-bounds memory access causing server crash / DoS.
- In certain configurations, higher impact outcomes may be possible.
## Affected
The provided references are Red Hat errata packages that include Xwayland components (not the full X.Org X server package list). From the reference content, the following RPMs are present in the affected/updated errata streams:
- xorg-x11-server-Xwayland-24.1.5-6.el10_1 (RHEL 10)
- xorg-x11-server-Xwayland-23.2.7-6.el9_7 (RHEL 9)
## Impact
- Confidentiality: potential memory disclosure (C:H).
- Integrity: potential memory corruption (I:H).
- Availability: potential crash/DoS (A:H).
- CVSS indicates high severity (7.8) with local access requirements (AV:L, AC:L, PR:L, UI:N).
## Mitigation
1. Patch/upgrade the relevant X.Org/Xwayland packages from the vendor errata referenced in your environment (e.g., RHSA-2026:11352, RHSA-2026:11369).
2. Reduce local attacker exposure to the X server (e.g., restrict access to the display/session and limit who can interact with the X socket).
3. Monitor for abnormal X server behavior consistent with malformed request handling (crashes/restarts and related service logs).
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-125