The vulnerability in the Linux kernel arises from an improper handling of a dentry in the overlay filesystem’s mkdir helper. After a successful vfs_mkdir() call the kernel debug path attempts to print the resulting dentry with the %pd format. Because vfs_mkdir() may free or replace the dentry on failure, the post‑call %pd can reference a dentry that no longer exists, resulting in a use‑after‑free that can crash the kernel.

All Linux kernel instances compiled with CONFIG_OVERLAY_FS enabled and with CONFIG_OVERLAY_FS_DEBUG active that have not yet incorporated commit fe497f0759e0 or a later patch are affected. The CVE entry does not list specific kernel versions, so the problem applies to any release lacking this fix.

The CVSS score of 4.7 indicates moderate severity. The EPSS score of less than 1% shows an extremely low probability of exploitation, and the vulnerability is not listed in the CISA KEV catalog. Exploitation would likely require local access to a system running the vulnerable kernel and the ability to trigger a mkdir operation under the overlay filesystem while debug logging is enabled. Given the limited configuration requirements and low exploitation probability, the overall risk is moderate, but a successful attack would result in a kernel crash.