---
id: CVE-2026-98136
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ntfs: bound $AttrDef table walk to the loaded table size

  ntfs_attr_find_in_attrdef() walks the in-memory $AttrDef table, but the
  loop condition bounds only the start o…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ntfs: bound $AttrDef table walk to the loaded table size

  ntfs_attr_find_in_attrdef() walks the in-memory $AttrDef table, but the
  loop condition bounds only the start o…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1e9ea7e04472d4e5e12e58c881eaacfb3e49b669 <
    3e2ae47b8ebc632c27e7843a4632d9a7c060885e
  - >-
    Linux >= 1e9ea7e04472d4e5e12e58c881eaacfb3e49b669 <
    c8504fc1245f5322af5fa5c325ab05f9cf792b87
  - Linux 7.1
published: '2026-09-25'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T11:17:45.043'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98136'
references:
  - url: 'https://git.kernel.org/stable/c/3e2ae47b8ebc632c27e7843a4632d9a7c060885e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c8504fc1245f5322af5fa5c325ab05f9cf792b87'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-25T11:06:38.811Z'
---

## Overview

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

ntfs: bound $AttrDef table walk to the loaded table size

ntfs_attr_find_in_attrdef() walks the in-memory $AttrDef table, but the
loop condition bounds only the start of each entry, not the whole entry:

	for (ad = vol->attrdef; (u8 *)ad - (u8 *)vol->attrdef <
			vol->attrdef_size && ad->type; ++ad)

struct attr_def is 160 bytes; the guard reads ad->type at offset 128 and
the loop body reads further fields. vol->attrdef is kvzalloc(i_size),
where i_size is the on-disk $AttrDef data size, checked in
load_and_init_attrdef() only as 0 < i_size <= 0x7fffffff. A volume whose
$AttrDef data size is smaller than one entry (e.g. 120 bytes) makes the
read of ad->type run past the allocation. Creating a file reaches this
through ntfs_attr_size_bounds_check() and reads out of bounds:

  BUG: KASAN: slab-out-of-bounds in ntfs_attr_find_in_attrdef+0x66/0xa0
  Read of size 4 at addr ffff888005833280 by task init/1
   ntfs_attr_find_in_attrdef
   ntfs_attr_size_bounds_check
   ntfs_attr_can_be_non_resident
   ntfs_attr_add

Require the whole entry to lie within attrdef_size in the loop guard, and
reject at mount a $AttrDef too small to hold one attr_def entry.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.