CVE-2026-33999A flaw was found in the X.Org X server.
Updated under an hour ago ()
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No exploitation reported and no EPSS estimate yet.
A flaw was found in the X.Org X server. This integer underflow vulnerability, specifically in the XKB compatibility map handling, allows an attacker with local or remote X11 server access to trigger a buffer read overrun. This can lead to memory-safety violations and potentially a denial of service (DoS) or other severe impacts.
- CVSS
- 7.8 HIGH (v3.1, NVD)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Weakness (CWE)
- CWE-191
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Not given
- NVD analysis
- Awaiting Analysis
- Record last updated
- Jul 15, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
No affected products are listed yet.
References
- https://access.redhat.com/errata/RHSA-2026:10739
- https://access.redhat.com/errata/RHSA-2026:11352
- https://access.redhat.com/errata/RHSA-2026:11369
- https://access.redhat.com/errata/RHSA-2026:11388
- https://access.redhat.com/errata/RHSA-2026:11656
- https://access.redhat.com/errata/RHSA-2026:11692
- https://access.redhat.com/errata/RHSA-2026:13414
- https://access.redhat.com/errata/RHSA-2026:19125
- https://access.redhat.com/errata/RHSA-2026:19342
- https://access.redhat.com/errata/RHSA-2026:19343
- https://access.redhat.com/errata/RHSA-2026:19344
- https://access.redhat.com/errata/RHSA-2026:20547
- https://access.redhat.com/errata/RHSA-2026:20555
- https://access.redhat.com/errata/RHSA-2026:20557
- https://access.redhat.com/errata/RHSA-2026:20558
- https://access.redhat.com/errata/RHSA-2026:20560
- https://access.redhat.com/errata/RHSA-2026:20561
- https://access.redhat.com/errata/RHSA-2026:20562
- https://access.redhat.com/errata/RHSA-2026:20563
- https://access.redhat.com/errata/RHSA-2026:20575
- https://access.redhat.com/errata/RHSA-2026:20576
- https://access.redhat.com/errata/RHSA-2026:20590
- https://access.redhat.com/errata/RHSA-2026:21699
- https://access.redhat.com/errata/RHSA-2026:21712
- https://access.redhat.com/errata/RHSA-2026:21715
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.