The Linux kernel’s raid bitmap handler reads bitmap pages from member disks without verifying that a disk is fully synchronized. Because the code only checks for raid_disk assignment and the Faulty flag, it can inadvertently read from spare disks that are still being rebuilt and do not contain valid bitmap data. This stale or uninitialized data is interpreted as dirty‑bit markers, which can corrupt the recovery logic and lead to loss or corruption of stored data. The flaw maps to a Programming Error (CWE‑821).

The vulnerability exists in the generic Linux kernel image and applies to any kernel that contains the unpatched bitmap‑reading logic in the md/md‑llbitmap subsystem. No specific kernel release or version is listed, so any distribution kernel that has not yet applied the change that adds an In_sync flag check remains potentially vulnerable.

The CVSS score is 7.0, indicating a high severity impact. The EPSS score is not available, but the available data suggest that the vulnerability’s exploitation requires a local privileged attacker who can influence the raid rebuild state or trigger a bitmap read while a disk is unsynchronized. Remote exploitation is unlikely because the flaw is exercised only during normal raid operations. The vulnerability is not listed in the CISA KEV catalog and no public exploit is currently known, so the likelihood of exploitation in the wild is moderate but not negligible.