CVE-2026-50258
CVE-2026-50258 · Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: stack buffer overflow in xkb key types due to unchecked shift levels
This page contains facts from public vulnerability sources. Check the original advisory before updating.
This page shows selected source facts. See the linked advisories for the complete description and affected versions.
A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. The X server has multiple stack buffers sized XkbMaxShiftLevel * XkbNumKbdGroups but CheckKeyTypes() does not verify or clamp non-canonical key types to XkbMaxShiftLevel. A client can change key types to excessive shift levels and trigger stack overflows. This is caused by an incomplete fix of CVE-2025-26597. This may be used to crash the server, or for privilege escalation if the X server runs as root.
CVSS 7.8 · High · EPSS 0.2% · Fix available
- Published
- Updated
Stack: system
Affected products and versions
red hat enterprise linux 10
- Versions
- ≥ 0:24.1.9-4.el10_2.2: Not affected (rpm)
No fix published
red hat enterprise linux 10.0 extended update support
- Versions
- ≥ 0:24.1.5-6.el10_0.1: Not affected (rpm)
No fix published
red hat enterprise linux 6 extended lifecycle support - extension
- Versions
- ≥ 0:1.1.0-25.el6_10.18: Not affected (rpm)
No fix published
red hat enterprise linux 7 extended lifecycle support
- Versions
- ≥ 0:1.20.4-35.el7_9: Not affected (rpm)
No fix published
red hat enterprise linux 7 extended lifecycle support
- Versions
- ≥ 0:1.8.0-36.el7_9.5: Not affected (rpm)
No fix published
red hat enterprise linux 8
- Versions
- ≥ 0:21.1.3-20.el8_10.2: Not affected (rpm)
No fix published
red hat enterprise linux 8
- Versions
- ≥ 0:1.20.11-28.el8_10.2: Not affected (rpm)
No fix published
red hat enterprise linux 8
- Versions
- ≥ 0:1.15.0-10.el8_10: Not affected (rpm)
No fix published
red hat enterprise linux 8.4 advanced mission critical update support
- Versions
- ≥ 0:1.20.10-5.el8_4: Not affected (rpm)
No fix published
red hat enterprise linux 8.4 advanced mission critical update support
- Versions
- ≥ 0:1.11.0-8.el8_4.16: Not affected (rpm)
No fix published
red hat enterprise linux 8.4 extended update support long-life add-on
- Versions
- ≥ 0:1.20.10-5.el8_4: Not affected (rpm)
No fix published
red hat enterprise linux 8.4 extended update support long-life add-on
- Versions
- ≥ 0:1.11.0-8.el8_4.16: Not affected (rpm)
No fix published
red hat enterprise linux 8.6 advanced mission critical update support
- Versions
- ≥ 0:1.20.11-8.el8_6: Not affected (rpm)
No fix published
red hat enterprise linux 8.6 advanced mission critical update support
- Versions
- ≥ 0:21.1.3-2.el8_6.7: Not affected (rpm)
No fix published
red hat enterprise linux 8.6 advanced mission critical update support
- Versions
- ≥ 0:1.12.0-6.el8_6.18: Not affected (rpm)
No fix published
red hat enterprise linux 8.6 extended update support long-life add-on
- Versions
- ≥ 0:1.20.11-8.el8_6: Not affected (rpm)
No fix published
red hat enterprise linux 8.6 extended update support long-life add-on
- Versions
- ≥ 0:21.1.3-2.el8_6.7: Not affected (rpm)
No fix published
red hat enterprise linux 8.6 extended update support long-life add-on
- Versions
- ≥ 0:1.12.0-6.el8_6.18: Not affected (rpm)
No fix published
red hat enterprise linux 8.8 telecommunications update service
- Versions
- ≥ 0:1.20.11-19.el8_8: Not affected (rpm)
No fix published
red hat enterprise linux 8.8 telecommunications update service
- Versions
- ≥ 0:21.1.3-13.el8_8.1: Not affected (rpm)
No fix published
red hat enterprise linux 8.8 telecommunications update service
- Versions
- ≥ 0:1.12.0-15.el8_8.18: Not affected (rpm)
No fix published
red hat enterprise linux 8.8 update services for sap solutions
- Versions
- ≥ 0:1.20.11-19.el8_8: Not affected (rpm)
No fix published
red hat enterprise linux 8.8 update services for sap solutions
- Versions
- ≥ 0:21.1.3-13.el8_8.1: Not affected (rpm)
No fix published
red hat enterprise linux 8.8 update services for sap solutions
- Versions
- ≥ 0:1.12.0-15.el8_8.18: Not affected (rpm)
No fix published
Original sources
- https://access.redhat.com/errata/RHSA-2026:26562
- https://access.redhat.com/errata/RHSA-2026:26566
- https://access.redhat.com/errata/RHSA-2026:26590
- https://access.redhat.com/errata/RHSA-2026:26610
- https://access.redhat.com/errata/RHSA-2026:26709
- https://access.redhat.com/errata/RHSA-2026:28923
- https://access.redhat.com/errata/RHSA-2026:29844
- https://access.redhat.com/errata/RHSA-2026:36083
- https://access.redhat.com/errata/RHSA-2026:36085
- https://access.redhat.com/errata/RHSA-2026:36086
- https://access.redhat.com/errata/RHSA-2026:36087
- https://access.redhat.com/errata/RHSA-2026:36632
- https://access.redhat.com/errata/RHSA-2026:36633
- https://access.redhat.com/errata/RHSA-2026:36634
- https://access.redhat.com/errata/RHSA-2026:36768
- https://access.redhat.com/errata/RHSA-2026:36791
- https://access.redhat.com/errata/RHSA-2026:36792
- https://access.redhat.com/errata/RHSA-2026:36798
- https://access.redhat.com/errata/RHSA-2026:38502
- https://access.redhat.com/errata/RHSA-2026:38810
- https://access.redhat.com/errata/RHSA-2026:46377
- https://access.redhat.com/errata/RHSA-2026:46382
- https://access.redhat.com/errata/RHSA-2026:46385
- https://nvd.nist.gov/vuln/detail/CVE-2026-50258