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
https://git.kernel.org/stable/c/4d8690dace005a38e6dbde9ecce2da3ad85c7c41
https://git.kernel.org/stable/c/7df1df6f40c0720d30206aa35c0343b962350e0d
https://git.kernel.org/stable/c/bf4ebdb19ff9b3cdf992b50715fe61633327416a
https://git.kernel.org/stable/c/e374f4e496fef8168784f93a4477d67be34485fd

Configurations

No configuration.

History

20 Jul 2026, 15:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8

19 Jul 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-19 16:17

Updated : 2026-07-20 15:17

NVD link : CVE-2026-64136

Mitre link : CVE-2026-64136

CVE.ORG link : CVE-2026-64136

JSON object : View

Products Affected

No product.

CWE

No CWE.

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