xwayland: Integer Underflow (Wrap or Wraparound)
CVE-2026-109092 is a high-severity integer underflow (wrap or wraparound) vulnerability in xwayland from X.Org, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists version 24.1.15 as the first without the flaw, so updating xwayland to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.17% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update xwayland to 24.1.15 or a later version.
- Update xorg-x11-server to 21.1.26 or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| X.Org | xwayland | before 24.1.15 | 24.1.15 |
| X.Org | xorg-x11-server | before 21.1.26 | 21.1.26 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (suse.de).
Official description
Incorrectly handled negative sizes when processing ProcXvShmPutImage requests in the X.Org xwayland before 24.1.15 and X Server before 21.1.26 could be used by local authenticated X clients to crash the X server or execute code.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Integer Underflow (Wrap or Wraparound)
The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.
More Integer Underflow (Wrap or Wraparound) vulnerabilities (CWE-191)
Timeline
- CVE record published.
References
Patches and release notes
Other vulnerabilities in xwayland
- 7.8 High severity
- 8.5 High severity
- 8.5 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
Recent Integer Underflow (Wrap or Wraparound) vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 9.2 Critical severity
- 7.5 High severity
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