Adam Bedard discovered that libx11 incorrectly handled certain XKB keyboard map replies. If a user were tricked into connecting to a malicious X server, a remote attacker could possibly use this issue to cause libx11 to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2026-88806) It was discovered that libx11 incorrectly handled certain X Input Method (XIM) messages.
USN-8913-1: libx11 vulnerabilities
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