Description
A flaw was identified in the X.Org X server’s X Keyboard (Xkb) extension where improper bounds checking in the XkbSetCompatMap() function can cause an unsigned short overflow. If an attacker sends specially crafted input data, the value calculation may overflow, leading to memory corruption or a crash.
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: 23 · as of 10 November 2026
- CWE
- CWE-190
Could this be exploited in your environment?
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