CVE-2025-40067: Linux

High severity, CVSS 7.8. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: reject index allocation if $BITMAP is empty but blocks exist Index allocation requires at least one bit in the $BITMAP attribute to track usage of index entries. If the bitmap is empty while index blocks are already present, this reflects on-disk corruption. syzbot triggered this condition using a malformed NTFS image. During a rename() operation involving a long filename (which spans multiple index entries), the empty bitmap allowed the name to be added without valid tracking. Subsequent deletion of the original entry failed with -ENOENT, due to unexpected index state. Reject such cases by verifying that the bitmap is not empty when index blocks exist.

Affected products

• Linux Linux: from 6.6.102, before 6.6.112 (fixed in 6.6.112); from 6.12.42, before 6.12.53 (fixed in 6.12.53); from 6.15.10, before 6.16 (fixed in 6.16); from 6.16.1, before 6.17 (fixed in 6.17); from 6.17, before 6.17.3 (fixed in 6.17.3)

Published 2025-10-28. Last modified 2026-07-30.