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.
Weakness
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Red Hat Enterprise Linux 9.4 Extended Update Support | RedHat | qemu-kvm-17:8.2.0-11.el9_4.18 | * |
| Red Hat OpenShift Container Platform 4.16 | RedHat | rhcos-416.94.202601071926-0 | * |
| Red Hat OpenShift Container Platform 4.17 | RedHat | rhcos-417.94.202601120213-0 | * |
| Red Hat OpenShift Container Platform 4.18 | RedHat | rhcos-418.94.202601071817-0 | * |
| Qemu | Ubuntu | devel | * |
| Qemu | Ubuntu | esm-infra-legacy/trusty | * |
| Qemu | Ubuntu | esm-infra/bionic | * |
| Qemu | Ubuntu | esm-infra/focal | * |
| Qemu | Ubuntu | esm-infra/xenial | * |
| Qemu | Ubuntu | jammy | * |
| Qemu | Ubuntu | noble | * |
| Qemu | Ubuntu | plucky | * |
| Qemu | Ubuntu | questing | * |