0.0
NA
CVE-2026-64383
smb: client: fix double-free in SMB2_flush() replay
Description

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double-free in SMB2_flush() replay SMB2_flush() keeps its response buffer bookkeeping across replay attempts. If a replayable flush response is received and the retry then fails before cifs_send_recv() stores a replacement response, flush_exit will free the stale response pointer a second time. Reinitialize resp_buftype and rsp_iov at the top of the replay loop so cleanup only acts on response state produced by the current attempt. This fixes a double-free without changing replay handling for successful requests.

INFO

Published Date :

July 25, 2026, 10:17 a.m.

Last Modified :

July 25, 2026, 10:17 a.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2026-64383 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Fix a double-free vulnerability in the SMB2_flush() function by reinitializing response bookkeeping.
  • Apply the patch for the Linux kernel SMB2_flush() vulnerability.
  • Reinitialize response bookkeeping at the start of the replay loop.
  • Ensure cleanup acts only on current attempt's response state.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-64383 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-64383 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-64383 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-64383 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jul. 25, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '433042a91f9373241307725b52de573933ffedbf', 'lessThan': '6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb', 'versionType': 'git'}, {'status': 'affected', 'version': '4f1fffa2376922f3d1d506e49c0fd445b023a28e', 'lessThan': '878757163eea684750107a31ea134c103863515d', 'versionType': 'git'}, {'status': 'affected', 'version': '4f1fffa2376922f3d1d506e49c0fd445b023a28e', 'lessThan': '3407240cde132a4b72d6429a2625a09a2f78adaf', 'versionType': 'git'}, {'status': 'affected', 'version': '4f1fffa2376922f3d1d506e49c0fd445b023a28e', 'lessThan': '013a9a3da46c5dabcf18f65ea6a47874ba12a15d', 'versionType': 'git'}, {'status': 'affected', 'version': '4f1fffa2376922f3d1d506e49c0fd445b023a28e', 'lessThan': '4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a', 'versionType': 'git'}, {'status': 'affected', 'version': '6.6.32', 'lessThan': '6.6.145', 'versionType': 'semver'}], 'programFiles': ['fs/smb/client/smb2pdu.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.8'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.8', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.96', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['fs/smb/client/smb2pdu.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double-free in SMB2_flush() replay SMB2_flush() keeps its response buffer bookkeeping across replay attempts. If a replayable flush response is received and the retry then fails before cifs_send_recv() stores a replacement response, flush_exit will free the stale response pointer a second time. Reinitialize resp_buftype and rsp_iov at the top of the replay loop so cleanup only acts on response state produced by the current attempt. This fixes a double-free without changing replay handling for successful requests.
    Added Reference https://git.kernel.org/stable/c/013a9a3da46c5dabcf18f65ea6a47874ba12a15d
    Added Reference https://git.kernel.org/stable/c/3407240cde132a4b72d6429a2625a09a2f78adaf
    Added Reference https://git.kernel.org/stable/c/4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a
    Added Reference https://git.kernel.org/stable/c/6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb
    Added Reference https://git.kernel.org/stable/c/878757163eea684750107a31ea134c103863515d
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.