X.Org Server Cursor Vulnerability Impacts Xephyr and Xwayland Users

CVSScvssV3_1: 7.8

The X.Org server, which is an important component of many Linux desktop environments for handling graphics hardware, windowing systems and input handling, was found to have a vulnerability affecting how it handles cursor data.

Specifically in the Xephyr and Xwayland components, which are used for nested and Wayland server X clients respectively, there is an issue where the cursor code uses the wrong data type when initializing the cursor private data. This causes the cursor bits type to overwrite the security context data.

An attacker could potentially leverage this to execute arbitrary code or escalate privileges. They would need to find a way to influence cursor data sent to the vulnerable X server component.

If you use a desktop environment like GNOME or KDE that relies on the X.Org server, make sure to update your system regularly when security updates are available. Software vendors have likely already addressed this vulnerability so keeping all components up-to-date is important for protection.

Being cautious of untrusted programs that could interact with your X server instance is also advisable. Verify authenticity when downloading software from untrusted sources. Staying on top of software and system updates is the best way to mitigate risks from vulnerabilities like this one.