CVE-2025-11234Qemu-kvm: vnc websocket handshake use-after-free

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.

Timeline

Scores

EPSS (exploitation in 30 days)

0.91% · top 40% of all CVEs (15 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.

Affected products

• qemu

  • affected 2.6.0 – < 10.1.2

• Red Hat · Red Hat Enterprise Linux 10

  • unaffected 18:10.0.0-14.el10_1.5 – < *

• Red Hat · Red Hat Enterprise Linux 8

  • unaffected 8100020251120003312.489197e6 – < *

• Red Hat · Red Hat Enterprise Linux 8

  • unaffected 8100020251202222937.489197e6 – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support

  • unaffected 8040020260916092751.522a0ee4 – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

  • unaffected 8040020260916092751.522a0ee4 – < *

• Red Hat · Red Hat Enterprise Linux 8.8 Telecommunications Update Service

  • unaffected 8080020260910092120.63b34585 – < *

• Red Hat · Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions

  • unaffected 8080020260910092120.63b34585 – < *

• Red Hat · Red Hat Enterprise Linux 9

  • unaffected 17:10.1.0-17.el9_8 – < *

• Red Hat · Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions

  • unaffected 17:6.2.0-11.el9_0.10 – < *

• Red Hat · Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

  • unaffected 17:7.2.0-14.el9_2.24 – < *

• Red Hat · Red Hat Enterprise Linux 9.4 Extended Update Support

  • unaffected 17:8.2.0-11.el9_4.18 – < *

• Red Hat · Red Hat Enterprise Linux 9.4 Extended Update Support

  • unaffected 17:8.2.0-11.el9_4.19 – < *

• Red Hat · Red Hat OpenShift Container Platform 4.12

  • unaffected 412.86.202608241157-0 – < *

• Red Hat · Red Hat OpenShift Container Platform 4.16

  • unaffected 416.94.202601071926-0 – < *

• Red Hat · Red Hat OpenShift Container Platform 4.17

  • unaffected 417.94.202601120213-0 – < *

• Red Hat · Red Hat OpenShift Container Platform 4.18

  • unaffected 418.94.202601071817-0 – < *

• Red Hat · Red Hat Enterprise Linux 6

  All versions: unaffected

• Red Hat · Red Hat Enterprise Linux 7

  All versions: unaffected

• Red Hat · Red Hat Enterprise Linux 7

  All versions: affected

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• EUVD EUVD-2025-32560 (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2025-11234](https://cveledger.app/badge/CVE-2025-11234.svg)](https://cveledger.app/cve/CVE-2025-11234)

Record last updated 5 Nov 2026, 14:47 UTC.