CVE-2026-64136

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().

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/13fb413ae22a37c69341918a6d651d19a9b0b9b7	Patch
https://git.kernel.org/stable/c/4d8690dace005a38e6dbde9ecce2da3ad85c7c41	Patch
https://git.kernel.org/stable/c/7585d4242f59185b084957fa077396e53dbf7c24
https://git.kernel.org/stable/c/7df1df6f40c0720d30206aa35c0343b962350e0d	Patch
https://git.kernel.org/stable/c/bf4ebdb19ff9b3cdf992b50715fe61633327416a	Patch
https://git.kernel.org/stable/c/e374f4e496fef8168784f93a4477d67be34485fd	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc2::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc3::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc4::::::

History

30 Oct 2026, 13:19

Type	Values Removed	Values Added
References		() https://git.kernel.org/stable/c/7585d4242f59185b084957fa077396e53dbf7c24 -

19 Oct 2026, 21:17

Type	Values Removed	Values Added
CWE		CWE-362

Information

Published : 2026-07-19 16:17

Updated : 2026-10-30 13:19

NVD link : CVE-2026-64136

Mitre link : CVE-2026-64136

CVE.ORG link : CVE-2026-64136

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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fields\")\nrefactored cifs code to change cifs_tcp_ses_lock for tc_lock around\ntc_count changes.\n\nThere was missing lock around tc_count increment inside\nsmb2_find_smb_sess_tcon_unlocked()."}], "lastModified": "2026-10-30T13:19:32.040", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "637728F8-A8CA-4DE9-8032-CAC1DE6B6B44", "versionEndExcluding": "6.6.142", "versionStartIncluding": "6.6.128"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FCC171CA-8EB3-4BBA-9598-7821641E468A", "versionEndExcluding": "6.12.92", "versionStartIncluding": "6.12.75"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "19854A53-434C-4733-8EA0-563B5BE89FB1", "versionEndExcluding": "6.18.34", "versionStartIncluding": "6.18.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", 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