libX11 XkbGetMap Reply Heap-based Buffer Overflow
Summary
| CVE | CVE-2026-88806 |
|---|---|
| State | PUBLISHED |
| Assigner | suse |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-21 14:17:22 UTC |
| Updated | 2026-09-22 19:40:05 UTC |
| Description | A malicious X server could exploit a buffer overflow in libX11 before 1.8.14 during handling of XkbGetMap overflowing the key_sym_map. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from [email protected]
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS: 0.001990000 probability, percentile 0.100040000 (date 2026-09-23)
Problem Types: CWE-122 | CWE-122 CWE-122 Heap-based buffer overflow
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H |
| 3.1 | CNA | CVSS | 7.5 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
RequiredScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| gitlab.freedesktop.org/xorg/lib/libx11/-/merge_requests/309 | [email protected] | gitlab.freedesktop.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Adam Bedard working with TrendAI Zero Day Initiative (en)
CNA: Claude:claude-opus-4-6 (en)
There are currently no legacy QID mappings associated with this CVE.