A concurrency bug in the Linux kernel’s memory migration path allows a destination page to be made visible before it is correctly re‑queued on the deferred split queue. The race triggers WARN messages in deferred_split_folio() and can silently discard fully mapped, under‑used pages. The flaw is a classic race condition (CWE‑362) involving improper synchronization between migration and split queue handling and also exemplifies a lost updates race (CWE‑367).

All Linux kernel releases that do not include commit 3bac01168982ec3e3bf87efdc1807c7933590a85 (or later) are affected. This impacts every Linux distribution that ships such a kernel, regardless of vendor or distribution name.

The CVSS score is 4.7 and the EPSS score is < 1%; the vulnerability is not listed in the CISA KEV catalog. Based on the description, it is inferred that exploitation would require a local or privileged context, but the CVE data does not explicitly state the required privilege level. Because the severity is lower, the risk is moderate; systems that cannot upgrade may face instability or the silent loss of fully mapped pages if the race is triggered.