CVE-2026-72207 PUBLISHED

ntfs: not change 0-byte $DATA attribute to non-resident

Assigner: Linux
Reserved: 09.08.2026 Published: 15.08.2026 Updated: 17.08.2026

In the Linux kernel, the following vulnerability has been resolved:

ntfs: not change 0-byte $DATA attribute to non-resident

When ntfs_resident_attr_resize() cannot grow a resident attribute in place, it retries after converting other resident attributes to non-resident to free space in the MFT recrord.

Do not select zero-length resident $DATA attributes for this conversion. fsck treats 0-byte non-resident $DATA attribute as corruptions.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 9.8

AV:N - ntfs_resident_attr_resize() is reached from VFS write/truncate/fallocate paths (ntfs_attr_expand, __ntfs_attr_truncate_vfs); fs/ntfs registers ntfs_export_ops, so remote NFS or ksmbd clients writing to an exported rw NTFS share can trigger the corrupting conversion without local shell access. AC:L - An attacker can deterministically pack an MFT record with a resident 0-byte $DATA attribute plus other resident attributes, then grow a different resident attribute to force -ENOSPC and select that $DATA for conversion; no races or victim-specific memory layout are required. PR:N - Exploitation requires only permission to write or truncate files on a mounted NTFS volume (local user with directory write access, authenticated SMB/NFS client, or guest/anonymous write on a misconfigured export); mounting is environmental setup, not a privilege needed during the trigger. UI:N - Once an administrator has rw-mounted and optionally exported the NTFS volume (or automounted dual-boot/shared storage), the attacker drives write/truncate operations that exhaust MFT record space; no further victim clicks, opens, or cooperative actions are required beyond that standing configuration. S:U - Impact is confined to on-disk NTFS $DATA metadata corruption and subsequent filesystem operation failure within the host kernel/filesystem security authority; this is standard local or network filesystem exploitation, not a VM escape or cross-authority sandbox breakout. C:H - Converting a 0-byte resident $DATA to non-resident writes structurally invalid on-disk metadata that ntfsck/fsck treat as corruption; subsequent attribute lookups and data reads on the affected inode parse attacker-influenced corrupt non-resident layout and may read beyond intended attribute bounds. I:H - The bug persistently corrupts MFT $DATA records by creating invalid 0-byte non-resident attributes, enabling attacker-steerable on-disk metadata modification beyond the intended filesystem state that repair tools flag as corruption and that can render affected files or volumes inconsistent across OSes. A:H - Corrupt 0-byte non-resident $DATA attributes cause fsck/ntfsck failures and can leave affected files or volumes unusable on remount or when accessed from Windows or Linux; persistent on-disk corruption that blocks reliable filesystem access scores Availability High.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to ceb49c37250125d418410988f2376ed4d57a6706 (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 0aad21570197973af4a1b25b3fb8ed3aeb9e7670 (excl.)
  • affected from 0 to 7.1.5 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • unaffected from 7.1.5 to 7.1.* (incl.)
  • unaffected from 7.2 to * (incl.)

References