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.
Problem types
Product status
2.6.0 before 10.1.2
Timeline
| 2025-09-30: | Reported to Red Hat. |
| 2025-09-30: | Made public. |
Credits
Red Hat would like to thank Grant Millar (Cylo) for reporting this issue.
References
access.redhat.com/security/cve/CVE-2025-11234
bugzilla.redhat.com/show_bug.cgi?id=2401209 (RHBZ#2401209)
