Xwayland: Use After Free
CVE-2025-62230 is a high-severity use after free vulnerability in Xwayland from X.Org, with a CVSS 3.1 base score of 7.3 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 24.1.9 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 0.28% 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 24.1.9 or a later version.
- Update X Server to 21.1.19 or a later version.
- Update Vios to 4.1.1.30 or a later version.
- Read the advisory on lists.x.org for workarounds and exact fixed builds.
Affected products and versions
Version data comes from the organisation that assigned the CVE; 3 further products are omitted here. 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
- LowLimited modification of data is possible.
- 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:L/A:H. Scored by CNA (redhat.com).
Official description
A flaw was discovered in the X.Org X server’s X Keyboard (Xkb) extension when handling client resource cleanup. The software frees certain data structures without properly detaching related resources, leading to a use-after-free condition. This can cause memory corruption or a crash when affected clients disconnect.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Patches and release notes
- openwall.com/lists/oss-security/2025/10/28/7Mailing List
Third-party and government advisories
- access.redhat.com/errata/RHSA-2025:19432Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19433Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19434Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19435Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19489Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19623Third Party Advisory
- access.redhat.com/errata/RHSA-2025:19909Third Party Advisory
- access.redhat.com/errata/RHSA-2025:20958Third Party Advisory
- access.redhat.com/errata/RHSA-2025:20960Third Party Advisory
- access.redhat.com/errata/RHSA-2025:20961Third Party Advisory
- access.redhat.com/errata/RHSA-2025:21035Third Party Advisory
- access.redhat.com/errata/RHSA-2025:22040Third Party Advisory
- access.redhat.com/errata/RHSA-2025:22041Third Party Advisory
- access.redhat.com/errata/RHSA-2025:22051Third Party Advisory
- access.redhat.com/errata/RHSA-2025:22055Third Party Advisory
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 Use After Free vulnerabilities
- 7.3 High severity
- 7.8 High severity
- 7.5 High severity
- 7.8 High severity
- 9.8 Critical severity
- 7.8 High severity
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