A defect in the Linux kernel’s XFS subsystem causes the log roundoff value to be set incorrectly when the superblock lacks a log stripe unit specification. The kernel defaults the roundoff to 512 bytes in environments where the physical sector size is 4096, which misaligns log entries and corrupts the internal log. During mounting or recovery, this manifests as CRC failures, failure to locate log tails, and unmountable file systems, potentially resulting in loss or corruption of stored data.

All Linux kernel distributions that incorporate the pre‑fix XFS code are affected; the vulnerability is present regardless of distribution, as it is a kernel bug. The specific kernel versions that have not integrated the commit that replaces the undersized l_iclog_roundoff logic are impacted. No explicit release list is provided, so any kernel running an old XFS implementation before the fix is vulnerable.

The CVSS score is 7.0, and EPSS data are unavailable. The flaw can cause critical data loss; it is not listed in the CISA KEV catalog. Likely exploitation requires local access to modify or recreate a filesystem superblock, either by using the flawed mkfs tool or by directly crafting a corrupt superblock. Consequently, the attack vector is inferred to be local privileged or root access; no confirmed remote exploitation path is documented in the available data.