Description
A flaw was discovered in the X.Org X server’s X Keyboard (Xkb) extension when handling client resource cleanup. The software frees certain data structures without properly detaching related resources, leading to a use-after-free condition. This can cause memory corruption or a crash when affected clients disconnect.
Affected products
x.org: x server; x.org: xwayland; ibm: vios; ibm: aix; debian: debian linux; redhat: enterprise linux; redhat: enterprise linux aus; redhat: enterprise linux els; redhat: enterprise linux eus; redhat: enterprise linux tus; redhat: enterprise linux update services for sap solutions
References10
- lists.x.org/archives/xorg-announce/2025-October/003635.html Mailing ListVendor Advisory
- www.openwall.com/lists/oss-security/2025/10/28/7 Mailing ListPatch
- access.redhat.com/errata/RHSA-2025:19432 Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19433 Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19434 Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19435 Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19489 Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19623 Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19909 Third Party Advisory
- access.redhat.com/errata/RHSA-2025:20958 Third Party Advisory
Metrics
- CVSS 3.1
-
7.3
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H - EPSS — exploit probability
- 0% percentile: 21 · as of 10 November 2026
- CWE
- CWE-416
Could this be exploited in your environment?
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