---
id: CVE-2026-46195
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  smb: client: validate dacloffset before building DACL pointers

  parse_sec_desc(), build_sec_desc(), and the chown path in
  id_mode_to_cifs_acl() all add the server-suppl…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  smb: client: validate dacloffset before building DACL pointers

  parse_sec_desc(), build_sec_desc(), and the chown path in
  id_mode_to_cifs_acl() all add the server-suppl…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-476
  - CWE-787
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 5.12, < 6.6.140'
  - 'linux_kernel >= 6.7, < 6.12.88'
  - 'linux_kernel >= 6.13, < 6.18.30'
  - 'linux_kernel >= 6.19, < 7.0.7'
  - linux_kernel = 7.1
patched:
  - linux_kernel 7.0.7
published: '2026-05-28'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:19:49.787'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-46195'
references:
  - url: 'https://git.kernel.org/stable/c/3b1ddba19e77ee35241cd27f16dc3e8d14e08db7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5de2665e913a10ad70aaeecf736b97276e83d995'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/8bd07e417b6bda67e317920584e48cb6ee442a8a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ba7f71b6161c0943dafc367565e5843d16b7d505'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c688f3ed73d31943334ad2139cb02ec49664322a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f98b48151cc502ada59d9778f0112d21f2586ca3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f9dc3be8f403c1216df73e57221f44b045e7ee0b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://access.redhat.com/errata/RHSA-2026:21556'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://access.redhat.com/errata/RHSA-2026:21706'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://access.redhat.com/errata/RHSA-2026:21745'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://access.redhat.com/security/cve/CVE-2026-46195'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2482606'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-784472.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46195.json
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
tags:
  - nvd
  - cve.org
epss: 0.00675
epssPercentile: 0.51986
ingestedAt: '2026-09-11T18:53:56.572Z'
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-10-16T15:20:56.572317Z'
---

## Overview

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

smb: client: validate dacloffset before building DACL pointers

parse_sec_desc(), build_sec_desc(), and the chown path in
id_mode_to_cifs_acl() all add the server-supplied dacloffset to pntsd
before proving a DACL header fits inside the returned security
descriptor.

On 32-bit builds a malicious server can return dacloffset near
U32_MAX, wrap the derived DACL pointer below end_of_acl, and then slip
past the later pointer-based bounds checks. build_sec_desc() and
id_mode_to_cifs_acl() can then dereference DACL fields from the wrapped
pointer in the chmod/chown rewrite paths.

Validate dacloffset numerically before building any DACL pointer and
reuse the same helper at the three DACL entry points.

## Affected

- `linux_kernel >= 5.12, < 6.6.140`
- `linux_kernel >= 6.7, < 6.12.88`
- `linux_kernel >= 6.13, < 6.18.30`
- `linux_kernel >= 6.19, < 7.0.7`
- `linux_kernel = 7.1`

## Remediation

Upgrade past the affected range:

- `linux_kernel 7.0.7`