---
id: CVE-2026-64387
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  smb: client: fix query directory replay double-free

  A response-bearing attempt can return a replayable error and free its
  response buffer
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  smb: client: fix query directory replay double-free

  A response-bearing attempt can return a replayable error and free its
  response buffer. If SMB2_query_directory_init…
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-415
  - CWE-1341
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 6.6.32, < 6.6.145'
  - 'linux_kernel >= 6.8.1, < 6.12.96'
  - 'linux_kernel >= 6.13, < 6.18.39'
  - 'linux_kernel >= 6.19, < 7.1.4'
  - linux_kernel = 6.8
patched:
  - linux_kernel 7.1.4
published: '2026-07-25'
updated: '2026-09-04'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64387'
references:
  - url: 'https://git.kernel.org/stable/c/00b0fa425941438b664950a8ee65dfba2def4336'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/1665f25b1dea30bf2d02e16245d203a944c9d994'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3317a5d015fca976475aa71df224056777316fde'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3409aedf3c81a810243da94164f6621c9d205c98'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9647492b5e41954be59d5157eddbcd4cdc1656f7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64387.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-64387'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2507046'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-64387'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64387'
  - url: >-
      https://lore.kernel.org/linux-cve-announce/2026072526-CVE-2026-64387-ff1a@gregkh/T
  - url: 'https://access.redhat.com/errata/RHSA-2026:67114'
  - url: 'https://access.redhat.com/errata/RHSA-2026:63128'
  - url: 'https://access.redhat.com/errata/RHSA-2026:63129'
  - url: 'https://access.redhat.com/errata/RHSA-2026:67720'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
  - score-dispute
epss: 0.00457
epssPercentile: 0.38992
ingestedAt: '2026-09-05T13:39:57.309Z'
scores:
  nvd: 9.8
  vendor: 7
---

## Overview

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

smb: client: fix query directory replay double-free

A response-bearing attempt can return a replayable error and free its
response buffer. If SMB2_query_directory_init() fails before the next send,
cleanup retains the previous buffer type and frees that response again.

Reset response bookkeeping before each attempt to prevent the stale free.

## Affected

- `linux_kernel >= 6.6.32, < 6.6.145`
- `linux_kernel >= 6.8.1, < 6.12.96`
- `linux_kernel >= 6.13, < 6.18.39`
- `linux_kernel >= 6.19, < 7.1.4`
- `linux_kernel = 6.8`

## Remediation

Upgrade past the affected range:

- `linux_kernel 7.1.4`

## Vendor advisories

- **RHSA-2026:67114** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux BaseOS EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0), Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0), Red Hat Enterprise Linux Real Time EUS (v. 10.0) · released 2026-09-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:67114)
- **RHSA-2026:63128** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10), Red Hat Enterprise Linux Real Time for NFV (v. 10), Red Hat Enterprise Linux Real Time (v. 10) · released 2026-09-04 · [advisory](https://access.redhat.com/errata/RHSA-2026:63128)
- **RHSA-2026:63129** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Real Time for NFV (v. 9), Red Hat Enterprise Linux Real Time (v. 9) · released 2026-09-04 · [advisory](https://access.redhat.com/errata/RHSA-2026:63129)
- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 9 · updated 2026-09-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64387.json)
- **RHSA-2026:67720** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6), Red Hat Enterprise Linux BaseOS EUS (v.9.6), Red Hat CodeReady Linux Builder EUS (v.9.6), Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6), Red Hat Enterprise Linux Real Time EUS (v.9.6) · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:67720)