SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2025-40067

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.

HIGH 7.8EPSS 0.15%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.15%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
0.15% probability · 5th percentile
CISA KEV
Not listed
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.