A flaw was found in the X servers request handling. Non-zero bytes to ignore in a clients request can cause the server to skip processing another clients request, potentially leading to a denial of service.
The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Xorg-server | Ubuntu | esm-infra/bionic | * |
| Xorg-server | Ubuntu | esm-infra/focal | * |
| Xorg-server | Ubuntu | esm-infra/xenial | * |
| Xorg-server | Ubuntu | jammy | * |
| Xorg-server | Ubuntu | noble | * |
| Xorg-server | Ubuntu | oracular | * |
| Xorg-server | Ubuntu | plucky | * |
| Xorg-server | Ubuntu | upstream | * |
| Xorg-server-hwe-16.04 | Ubuntu | esm-infra/xenial | * |
| Xorg-server-hwe-18.04 | Ubuntu | esm-infra/bionic | * |
| Xwayland | Ubuntu | jammy | * |
| Xwayland | Ubuntu | noble | * |
| Xwayland | Ubuntu | oracular | * |
| Xwayland | Ubuntu | plucky | * |
| Xwayland | Ubuntu | upstream | * |
Locking is a type of synchronization behavior that ensures that multiple independently-operating processes or threads do not interfere with each other when accessing the same resource. All processes/threads are expected to follow the same steps for locking. If these steps are not followed precisely - or if no locking is done at all - then another process/thread could modify the shared resource in a way that is not visible or predictable to the original process. This can lead to data or memory corruption, denial of service, etc.