A use-after-free flaw was found in X.Org and Xwayland. When changing an alarm, the values of the change mask are evaluated one after the other, changing the trigger values as requested, and eventually, SyncInitTrigger() is called. If one of the changes triggers an error, the function will return early, not adding the new sync object, possibly causing a use-after-free when the alarm eventually triggers.
https://bugzilla.redhat.com/show_bug.cgi?id=2345251
https://access.redhat.com/security/cve/CVE-2025-26601
https://access.redhat.com/errata/RHSA-2025:2880
https://access.redhat.com/errata/RHSA-2025:2879
https://access.redhat.com/errata/RHSA-2025:2875
https://access.redhat.com/errata/RHSA-2025:2874
https://access.redhat.com/errata/RHSA-2025:2873
https://access.redhat.com/errata/RHSA-2025:2866
https://access.redhat.com/errata/RHSA-2025:2865
https://access.redhat.com/errata/RHSA-2025:2862
https://access.redhat.com/errata/RHSA-2025:2861