CVE-2025-11234

Publication date 3 October 2025

Last updated 8 October 2025


Ubuntu priority

Cvss 3 Severity Score

7.5 · High

Score breakdown

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.

Read the notes from the security team

Status

Package Ubuntu Release Status
qemu 25.04 plucky
Vulnerable, fix deferred
24.04 LTS noble
Vulnerable, fix deferred
22.04 LTS jammy
Vulnerable, fix deferred
20.04 LTS focal
Vulnerable, fix deferred
18.04 LTS bionic
Vulnerable, fix deferred
16.04 LTS xenial
Vulnerable, fix deferred
14.04 LTS trusty
Vulnerable, fix deferred

Notes


mdeslaur

as of 2025-10-07, the proposed fix has not yet been committed

Severity score breakdown

Parameter Value
Base score 7.5 · High
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H