---
id: CVE-2026-89782
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  fs/ntfs3: reject restart table growth beyond U16_MAX entries

  During $LogFile replay, log_replay() indexes the transaction table by the
  transact_id taken from the log r…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  fs/ntfs3: reject restart table growth beyond U16_MAX entries

  During $LogFile replay, log_replay() indexes the transaction table by the
  transact_id taken from the log r…
severity: high
cvss: 8.4
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 <
    caa0ec3fc44a13d7c21d78e4722f4f05f87ccf56
  - >-
    Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 <
    339e59996ff193adcf1c438cf05f19e753beb3a7
  - >-
    Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 <
    ecde45cd81dc28f5696c312c5ce5a509962e9ab1
  - >-
    Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 <
    be218a01aadffe33ed4fc73e25276d676ebbd09d
  - >-
    Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 <
    aad605a450611e2a7b7cf9dd5724004d39192bfb
  - >-
    Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 <
    967a5ff8a614d10126b6d46db1ac040948d6cb42
  - >-
    Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 <
    111f8d74a19d85942ecbb3aba78f6f3c88e59391
  - Linux 5.15
published: '2026-09-16'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T15:18:08.577'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89782'
references:
  - url: 'https://git.kernel.org/stable/c/111f8d74a19d85942ecbb3aba78f6f3c88e59391'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/339e59996ff193adcf1c438cf05f19e753beb3a7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/967a5ff8a614d10126b6d46db1ac040948d6cb42'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/aad605a450611e2a7b7cf9dd5724004d39192bfb'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/be218a01aadffe33ed4fc73e25276d676ebbd09d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/caa0ec3fc44a13d7c21d78e4722f4f05f87ccf56'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ecde45cd81dc28f5696c312c5ce5a509962e9ab1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-16T08:52:29.595Z'
epss: 0.0019
epssPercentile: 0.07647
---

## Overview

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

fs/ntfs3: reject restart table growth beyond U16_MAX entries

During $LogFile replay, log_replay() indexes the transaction table by the
transact_id taken from the log record header.  check_log_rec() only
verifies that transact_id is non-zero and properly aligned, not its
magnitude, so a crafted image can request an arbitrarily large index.

alloc_rsttbl_from_idx() grows the table to cover that index via
extend_rsttbl(), which passes the new entry count to init_rsttbl():

	rt = init_rsttbl(esize, used + add);

used + add is computed as u32 but init_rsttbl() takes a u16, and the
count is stored in struct RESTART_TABLE as a __le16.  When used + add
exceeds U16_MAX it is truncated, init_rsttbl() allocates a table far
smaller than the index requires, and alloc_rsttbl_from_idx() then
dereferences and writes at the original, untruncated offset -- an
out-of-bounds access past the allocation, reachable by mounting a
crafted NTFS image.

 BUG: KASAN: use-after-free in alloc_rsttbl_from_idx (fs/ntfs3/fslog.c:950)
 Read of size 4 at addr ffff8880327ffff8 by task exploit
  alloc_rsttbl_from_idx (fs/ntfs3/fslog.c:950)
  log_replay (fs/ntfs3/fslog.c:4562)
  ntfs_loadlog_and_replay (fs/ntfs3/fsntfs.c:324)
  ntfs_fill_super (fs/ntfs3/super.c:1393)
  get_tree_bdev_flags
  vfs_get_tree
  path_mount
  __x64_sys_mount

A restart table is limited to U16_MAX entries by its __le16 count, so a
larger growth request is invalid input.  Reject it in extend_rsttbl();
all callers already handle a NULL return.

## Remediation

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