---
id: CVE-2026-64597
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  smb: client: fix double-free in SMB2_close() replay

  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 double-free in SMB2_close() replay

  A response-bearing attempt can return a replayable error and free its
  response buffer. If SMB2_close_init() fails b…
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'
published: '2026-08-06'
updated: '2026-08-08'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64597'
references:
  - url: 'https://git.kernel.org/stable/c/037511726228aaf165c7067ff2bfc88eaecdf1f3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/0aa97edf7c347c0f54e7e60c4740574b8120c66a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b18ed621dbfceecea5539848cddcb9272c9a61e1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d15d83125007f673aec4323e1bbbaaffbe87ea13'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f96e1cdcb63ed3321142ff2fcdf784e32cda8fee'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64597.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-64597'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2511932'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-64597'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64597'
  - url: >-
      https://lore.kernel.org/linux-cve-announce/2026080652-CVE-2026-64597-760b@gregkh/T
  - url: 'https://access.redhat.com/errata/RHSA-2026:64775'
  - url: 'https://access.redhat.com/errata/RHSA-2026:66180'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
  - score-dispute
epss: 0.00359
epssPercentile: 0.29722
ingestedAt: '2026-08-08T21:30:13.297Z'
vendor: Red Hat
product: Red Hat Enterprise Linux BaseOS (v. 10)
affected:
  - enterprise_linux 9
  - enterprise_linux_for_nvidia 26
  - openshift_container_platform 4
  - enterprise_linux_appstream_v_10
  - enterprise_linux_baseos_v_10
  - enterprise_linux_codeready_linux_builder_v_10
  - enterprise_linux_real_time_for_nfv_v_10
  - enterprise_linux_real_time_v_10
patched:
  - enterprise_linux_appstream_v_10
  - enterprise_linux_baseos_v_10
  - enterprise_linux_codeready_linux_builder_v_10
  - enterprise_linux_real_time_for_nfv_v_10
  - enterprise_linux_real_time_v_10
cwe:
  - CWE-415
scores:
  nvd: 9.8
  vendor: 7
---

## Overview

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

smb: client: fix double-free in SMB2_close() replay

A response-bearing attempt can return a replayable error and free its
response buffer. If SMB2_close_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.

## Remediation

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

## Vendor advisories

- **RHSA-2026:64775** · 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 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:64775)
- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 9, Red Hat Enterprise Linux for NVIDIA 26, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 9, Red Hat Enterprise Linux for NVIDIA 26 · updated 2026-09-10 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64597.json)
- **RHSA-2026:66180** · 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 2026-09-10 · [advisory](https://access.redhat.com/errata/RHSA-2026:66180)