Public vulnerability disclosure
CVE-2025-11234
Qemu-kvm: vnc websocket handshake use-after-free
publishedCWE-416
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.
Technical severity7.5 highCVSS 3.1 · CNA: redhat
Published2025-10-03Source updated 2026-11-05
Collected2026-11-052 attributed sources
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
qemu
https://gitlab.com/qemu-project/qemu |
≥ 2.6.0; < 10.1.2 (affected, semver)
Other versions: unaffected |
CNA: redhat |
| Red Hat Enterprise Linux 10 Red Hat qemu-kvm
https://access.redhat.com/downloads/content/package-browser/ |
≥ 18:10.0.0-14.el10_1.5; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8 Red Hat virt-devel:rhel
https://access.redhat.com/downloads/content/package-browser/ |
≥ 8100020251120003312.489197e6; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8 Red Hat virt:rhel
https://access.redhat.com/downloads/content/package-browser/ |
≥ 8100020251202222937.489197e6; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support Red Hat virt:rhel
https://access.redhat.com/downloads/content/package-browser/ |
≥ 8040020260916092751.522a0ee4; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On Red Hat virt:rhel
https://access.redhat.com/downloads/content/package-browser/ |
≥ 8040020260916092751.522a0ee4; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.8 Telecommunications Update Service Red Hat virt:rhel
https://access.redhat.com/downloads/content/package-browser/ |
≥ 8080020260910092120.63b34585; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions Red Hat virt:rhel
https://access.redhat.com/downloads/content/package-browser/ |
≥ 8080020260910092120.63b34585; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9 Red Hat qemu-kvm
https://access.redhat.com/downloads/content/package-browser/ |
≥ 17:10.1.0-17.el9_8; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions Red Hat qemu-kvm
https://access.redhat.com/downloads/content/package-browser/ |
≥ 17:6.2.0-11.el9_0.10; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions Red Hat qemu-kvm
https://access.redhat.com/downloads/content/package-browser/ |
≥ 17:7.2.0-14.el9_2.24; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9.4 Extended Update Support Red Hat qemu-kvm
https://access.redhat.com/downloads/content/package-browser/ |
≥ 17:8.2.0-11.el9_4.18; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9.4 Extended Update Support Red Hat qemu-kvm
https://access.redhat.com/downloads/content/package-browser/ |
≥ 17:8.2.0-11.el9_4.19; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.12 Red Hat openshift/ose-rhel-coreos-8
https://access.redhat.com/downloads/content/package-browser/ |
≥ 412.86.202608241157-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.16 Red Hat openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/ |
≥ 416.94.202601071926-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.17 Red Hat openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/ |
≥ 417.94.202601120213-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.18 Red Hat openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/ |
≥ 418.94.202601071817-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 6 Red Hat qemu-kvm
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Enterprise Linux 7 Red Hat qemu-kvm
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Enterprise Linux 7 Red Hat qemu-kvm-ma
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA: redhat |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://access.redhat.com/errata/RHSA-2025:23228CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:0326CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:0332CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:0702CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:1831CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:18772CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:22147CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3077CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3165CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:5578CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:59831CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:68513CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:69131CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2025-11234CNA: redhat · vdb-entry, x_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2401209CNA: redhat · issue-tracking, x_refsource_REDHAT
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