During netfs copy-to-cache operations the Linux kernel marks a folio with PG_private_2 before attempting to append it to the copy-to-cache rolling buffer. If that append fails, the folio ceases to be queued for cache writeback and its reference never released. This oversight can leave a private page reference lingering in kernel memory, which may lead to resource exhaustion or unintended kernel state if not cleaned up promptly. This is an instance of a missing reference cleanup weakness, classified as CWE-404.

The flaw affected all Linux kernel releases before the applied patch. It was discovered by users reporting that netfs could leave dangling private page references when a copy‑to‑cache append fails. The fix has been incorporated by the core Linux maintainers and is present in current stable kernels distributed by all major Linux vendors.

The vulnerability is not listed in CISA KEV and no EPSS score is available, suggesting limited public exploitation data. Based on the description, it is inferred that an attacker with local execution or elevated privileges could exploit it to cause memory corruption or resource exhaustion, potentially leading to denial-of-service. The risk is therefore considered moderate to high until the kernel is updated to the patched version.