CVE-2026-64136
smb: client: protect tc_count increment in smb2_find_smb_sess_tcon_unlocked()
Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: protect tc_count increment in smb2_find_smb_sess_tcon_unlocked() Commit 96c4af418586 ("cifs: Fix locking usage for tcon fields") refactored cifs code to change cifs_tcp_ses_lock for tc_lock around tc_count changes. There was missing lock around tc_count increment inside smb2_find_smb_sess_tcon_unlocked().
INFO
Published Date :
July 19, 2026, 4:17 p.m.
Last Modified :
July 19, 2026, 4:17 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-64136
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
- Apply the security patch provided by the vendor.
- Update the Linux kernel to the latest stable release.
- Verify the integrity of the kernel modules.
- Reboot the system after applying updates.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-64136.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-64136 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-2026-64136
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-2026-64136 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-64136 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. 19, 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': '953953abb66e52c224057ab91e404284fefeab62', 'lessThan': '7df1df6f40c0720d30206aa35c0343b962350e0d', 'versionType': 'git'}, {'status': 'affected', 'version': '601dd3b79769b38d30b693c40afdb2a4b7edf9d0', 'lessThan': '13fb413ae22a37c69341918a6d651d19a9b0b9b7', 'versionType': 'git'}, {'status': 'affected', 'version': '3969db6b22e3d90d8c5f22ac1a7fe0350a94c136', 'lessThan': 'bf4ebdb19ff9b3cdf992b50715fe61633327416a', 'versionType': 'git'}, {'status': 'affected', 'version': '96c4af418586ee9a6aab61738644366426e05316', 'lessThan': 'e374f4e496fef8168784f93a4477d67be34485fd', 'versionType': 'git'}, {'status': 'affected', 'version': '96c4af418586ee9a6aab61738644366426e05316', 'lessThan': '4d8690dace005a38e6dbde9ecce2da3ad85c7c41', 'versionType': 'git'}, {'status': 'affected', 'version': '8c59eeeeffa1524ef57e173a89a1a3ff539888d5', 'versionType': 'git'}, {'status': 'affected', 'version': '6.6.128', 'lessThan': '6.6.142', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.12.75', 'lessThan': '6.12.92', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.18.16', 'lessThan': '6.18.34', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.19.6', 'lessThan': '6.20', 'versionType': 'semver'}], 'programFiles': ['fs/smb/client/smb2transport.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '7.0'}, {'status': 'unaffected', 'version': '0', 'lessThan': '7.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.142', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.92', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.34', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.11', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['fs/smb/client/smb2transport.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: smb: client: protect tc_count increment in smb2_find_smb_sess_tcon_unlocked() Commit 96c4af418586 ("cifs: Fix locking usage for tcon fields") refactored cifs code to change cifs_tcp_ses_lock for tc_lock around tc_count changes. There was missing lock around tc_count increment inside smb2_find_smb_sess_tcon_unlocked(). Added Reference https://git.kernel.org/stable/c/13fb413ae22a37c69341918a6d651d19a9b0b9b7 Added Reference https://git.kernel.org/stable/c/4d8690dace005a38e6dbde9ecce2da3ad85c7c41 Added Reference https://git.kernel.org/stable/c/7df1df6f40c0720d30206aa35c0343b962350e0d Added Reference https://git.kernel.org/stable/c/bf4ebdb19ff9b3cdf992b50715fe61633327416a Added Reference https://git.kernel.org/stable/c/e374f4e496fef8168784f93a4477d67be34485fd