RHSA-2026:98564: Important: libX11 security update
Published Nov 11, 2026
·Updated
The libX11 packages contain the core X11 protocol client library.Security Fix(es): libX11: libX11: Heap-based buffer overflow via malicious X server (CVE-2026-88806) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Affected Software
0 affected components
Event History
Nov 11, 2026
Advisory Published
via Red Hat·12:00 AM
Data Sourced
via Red Hat·12:00 AM
RemedyDescriptionAffected Software
Frequently Asked Questions
1
What must an attacker control to exploit this issue?
The vulnerability is triggered through a malicious X server. An attacker would need a libX11 client to connect to an X server under the attacker's control.
2
Which systems should be prioritized for remediation?
Prioritize systems running applications that use the libX11 X11 client library and may connect to untrusted or attacker-controlled X servers. The issue is classified as Important in the referenced Red Hat security advisory.