Affected: AlmaLinux:10: qemu-guest-agent, AlmaLinux:10: qemu-img, AlmaLinux:10: qemu-kvm, AlmaLinux:10: qemu-kvm-audio-pa, AlmaLinux:10: qemu-kvm-block-blkio, AlmaLinux:10: qemu-kvm-block-curl, AlmaLinux:10: qemu-kvm-block-rbd, AlmaLinux:10: qemu-kvm-common, AlmaLinux:10: qemu-kvm-core, AlmaLinux:10: qemu-kvm-device-display-virtio-gpu and 10 more

Kernel-based Virtual Machine (KVM) is a full virtualization solution for Linux on a variety of architectures. The qemu-kvm packages provide the user-space component for running virtual machines that use KVM.

Security Fix(es):

* qemu-kvm: VNC WebSocket handshake use-after-free (CVE-2025-11234)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

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.

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.

Affected: openEuler:20.03-LTS-SP4: qemu

QEMU is a FAST! processor emulator using dynamic translation to achieve good emulation speed. Security Fix(es):

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.(CVE-2025-11234)

qemu-10.1.3-1.1 on GA media

qemu-kvm: VNC WebSocket handshake use-after-free

Security update for qemu

Affected: Ubuntu:Pro:18.04:LTS: qemu, Ubuntu:Pro:20.04:LTS: qemu, Ubuntu:22.04:LTS: qemu, Ubuntu:24.04:LTS: qemu, Ubuntu:25.10: qemu

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.

Ein entfernter, anonymer Angreifer kann eine Schwachstelle in QEMU ausnutzen, um einen Denial of Service Angriff durchzuführen.