The vulnerability exists in the GLX component of the X.Org X11 server, where the interface does not verify that incoming data sizes remain within allocated buffer limits during large rendering requests. This oversight allows a local authenticated client to send a crafted request, triggering a heap‑based overflow that can lead to arbitrary code execution with the privileges of the X server. If exploitation fails to achieve code execution, the overflow can still corrupt memory and cause the server to crash, resulting in a denial of service.

The affected products are the X.org X11 server (xorg-x11-server) and XWayland, with vulnerable versions before 21.1.25 for the X11 server and before 24.1.14 for XWayland. Update both to the latest patched releases when available. If updates are not feasible, restrict authorized clients to reduce risk.

The CVSS score of 8.5 indicates high severity. The EPSS score is not available, so exploitation probability cannot be quantified at present, and the vulnerability is not listed in CISA KEV. The flaw is exploitable only by an authenticated local user. Based on the description, the likely attack vector is a local authenticated client that has permission to access the X server, which could be a legitimate user running graphical applications. Because the vulnerability requires local access, the risk is limited to machines with compromised or malicious local accounts.