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.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 03 Oct 2025 12:30:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

threat_severity

Moderate


Fri, 03 Oct 2025 10:45:00 +0000

Type Values Removed Values Added
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.
Title Qemu-kvm: vnc websocket handshake use-after-free
First Time appeared Redhat
Redhat advanced Virtualization
Redhat enterprise Linux
Redhat openshift
Redhat rhivos
Weaknesses CWE-416
CPEs cpe:/a:redhat:advanced_virtualization:8::el8
cpe:/a:redhat:openshift:4
cpe:/o:redhat:enterprise_linux:10
cpe:/o:redhat:enterprise_linux:6
cpe:/o:redhat:enterprise_linux:7
cpe:/o:redhat:enterprise_linux:8
cpe:/o:redhat:enterprise_linux:9
cpe:/o:redhat:rhivos:1
Vendors & Products Redhat
Redhat advanced Virtualization
Redhat enterprise Linux
Redhat openshift
Redhat rhivos
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2025-10-03T10:30:34.427Z

Reserved: 2025-10-01T17:03:04.737Z

Link: CVE-2025-11234

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2025-10-03T11:15:30.437

Modified: 2025-10-03T11:15:30.437

Link: CVE-2025-11234

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-09-30T12:18:00Z

Links: CVE-2025-11234 - Bugzilla

cve-icon OpenCVE Enrichment

No data.