Skip to main content
VulnerabilityPublished Updated

CVE-2026-33999: Red Hat Enterprise Linux 10 · Integer Underflow

Affects Red Hat Enterprise Linux 10Source CVE Database V5

0
Compare

Not known to be exploited · CVSS 7.8 High · patch available : patch Red Hat Enterprise Linux 10 soon.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score
7.8High
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 23 Apr 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponized: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

What to do

Affected software

ProductAffectedFixed in
Red Hat Enterprise Linux 10xorg-x11-server-XwaylandAffected–Fixed in–
Red Hat Enterprise Linux 10xorg-x11-server-XwaylandAffected–Fixed in–
Red Hat Enterprise Linux 10.0 Extended Update Supportxorg-x11-server-XwaylandAffected–Fixed in–
Red Hat Enterprise Linux 6 Extended Lifecycle Support - EXTENSIONtigervncAffected–Fixed in–
Red Hat Enterprise Linux 7 Extended Lifecycle Supportxorg-x11-serverAffected–Fixed in–
Red Hat Enterprise Linux 7 Extended Lifecycle SupporttigervncAffected–Fixed in–

AI-suggested

Red Hat has released official security updates that address this vulnerability. Users should apply the updates provided in Red Hat Enterprise Linux advisories RHSA-2026:10739 and RHSA-2026:11352. These updates include fixes to the xorg-x11-server-Xwayland and tigervnc packages. Patch status is confirmed by the vendor advisory, and applying these updates will remediate the vulnerability. No additional mitigation steps are indicated by the vendor advisory.

Description

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.

References

Community reviews

Loading reviews…