CVE-2025-11234 (GCVE-0-2025-11234)

Vulnerability from cvelistv5 – Published: 2025-10-03 10:30 – Updated: 2026-01-15 18:57
VLAI?
Title
Qemu-kvm: vnc websocket handshake use-after-free
Summary
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.
Severity ?
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
Assigner
References
https://access.redhat.com/errata/RHSA-2025:23228 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:0326 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:0332 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2025-11234 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2401209 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version
Affected: 2.6.0 , < 10.1.2 (semver)
    Red Hat Red Hat Enterprise Linux 9.4 Extended Update Support Unaffected: 17:8.2.0-11.el9_4.18 , < * (rpm)
    cpe:/a:redhat:rhel_eus:9.4::appstream
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    Red Hat Red Hat OpenShift Container Platform 4.16 Unaffected: 416.94.202601071926-0 , < * (rpm)
    cpe:/a:redhat:openshift:4.16::el9
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    Red Hat Red Hat OpenShift Container Platform 4.18 Unaffected: 418.94.202601071817-0 , < * (rpm)
    cpe:/a:redhat:openshift:4.18::el9
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    Red Hat Red Hat Enterprise Linux 10     cpe:/o:redhat:enterprise_linux:10
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    Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
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    Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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    Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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    Red Hat Red Hat Enterprise Linux 8     cpe:/o:redhat:enterprise_linux:8
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    Red Hat Red Hat Enterprise Linux 9     cpe:/o:redhat:enterprise_linux:9
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Credits
Red Hat would like to thank Grant Millar (Cylo) for reporting this issue.
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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