CVE-2025-11234
Medium
Elevated severity or exploit probability.
CVSS base
7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS — probability of exploitation (30 days)
0.9%
56.8th percentile
CISA KEV
Not listed
Weakness / dates
CWE-416
Published 2025-10-03 · modified 2026-09-21
Description
A flaw was found in QEMU. If the QIOChannelWebsock object is freed while it is waiting to complete a handshake, a GSource is leaked. This can lead to the callback firing later on and triggering a use-after-free in the use of the channel. This can be abused by a malicious client with network access to the VNC WebSocket port to cause a denial of service during the WebSocket handshake prior to the VNC client authentication.
References
- https://access.redhat.com/errata/RHSA-2025:23228
- https://access.redhat.com/errata/RHSA-2026:0326
- https://access.redhat.com/errata/RHSA-2026:0332
- https://access.redhat.com/errata/RHSA-2026:0702
- https://access.redhat.com/errata/RHSA-2026:1831
- https://access.redhat.com/errata/RHSA-2026:18772
- https://access.redhat.com/errata/RHSA-2026:22147
- https://access.redhat.com/errata/RHSA-2026:3077
- https://access.redhat.com/errata/RHSA-2026:3165
- https://access.redhat.com/errata/RHSA-2026:5578
- https://access.redhat.com/errata/RHSA-2026:59831
- https://access.redhat.com/errata/RHSA-2026:68513
- https://access.redhat.com/errata/RHSA-2026:69131
- https://access.redhat.com/security/cve/CVE-2025-11234
- https://bugzilla.redhat.com/show_bug.cgi?id=2401209