CVE-2026-88807

A flaw was found in libXrender. Malicious X servers can exploit a heap overflow vulnerability in the RenderQueryPictFormats function. This allows them to inject arbitrary code into connected X clients, potentially leading to unauthorized control over the client's system.

This vulnerability is rated as having an Important impact because successful exploitation can allow arbitrary code execution with the permissions of the calling client application, crossing the trust boundary from the display server to the client host. However, triggering the flaw requires an X11 client application to connect to an untrusted or compromised X server, such as via insecure remote X11 forwarding. In typical Red Hat Enterprise Linux environments, client applications connect exclusively to trusted local display servers, which substantially limits practical exposure.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.