What is CVE-2026-64140?

CVE-2026-64140 is a High severity Linux kernel vulnerability with a CVSS score of 7.5 out of 10, classified as a NULL Pointer Dereference flaw (CWE-476), affecting Linux kernel versions from 7.0 onward and patched in 7.0.11 and 7.1. CVE-2026-64140 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-64140?

CVE-2026-64140 has a CVSS score of 7.5 out of 10, rated High severity. The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Is there a patch available for CVE-2026-64140?

Yes, CVE-2026-64140 has been patched. Fixed versions include 7.0.11 and 7.1. If you are running Linux kernel 7.0 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-64140 actively exploited?

CVE-2026-64140 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is NULL Pointer Dereference (CWE-476)?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/476.html

CVE-2026-64140

High

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix null pointer dereference in proc_show_files() When a SMB2 client opens a file with a durable v2 handle and then issues SMB2 SESSION_LOGOFF, session_fd_check() clears fp->tcon = NULL on the reconnectable file pointer but leaves the fp registered in global_ft.idr until the durable scavenger fires (up to fp->durable_timeout seconds later). During that window any read of /proc/fs/ksmbd/files (mode 0400) panics the kernel because proc_show_files() walks global_ft.idr and unconditionally dereferences fp->tcon->id with no NULL guard. Reproducer requires only a successful SMB2 SESSION_SETUP and a share configured with 'durable handles = yes'. KASAN report on mainline 70390501d194: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:proc_show_files+0x118/0x740 Call Trace: proc_show_files+0x118/0x740 seq_read_iter+0x4ef/0xe10 proc_reg_read_iter+0x1b7/0x280 ... Guard the dereference. A durable-disconnected fp legitimately has no tcon; report its tree id as 0 rather than oopsing.

Package Linux Kernel

Published 2026-07-19

Last modified 2026-08-18

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.5

out of 10

High

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Vector string

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness type

CWE-476

CVE-2026-64140 is a NULL Pointer Dereference vulnerability

What is NULL Pointer Dereference?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE

Affected versions

Linux kernel versions 7.0 and later are affected. Fixed in 7.0.11, 7.1 and their respective stable series.

Affected from

≥ 7.0

Fixed in

✓ 7.0.11 7.0.x ✓ 7.1

References

2 total

Kernel Git
https://git.kernel.org/stable/c/8eab081627b67216d1c8f638b68289b500dc9a6b

Patch
Kernel Git
https://git.kernel.org/stable/c/904901561e61a2b559070b20c74a8c95491f30aa

Patch

Details

CVE ID CVE-2026-64140

Severity High

CVSS score 7.5 / 10

CVSS version 3.1

Published 2026-07-19

Modified 2026-08-18

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-64140?

CVE-2026-64140 is a High severity Linux kernel vulnerability with a CVSS score of 7.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 7.0 onward and has been patched in 7.0.11 and 7.1. CVE-2026-64140 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-64140?

CVE-2026-64140 has a CVSS score of 7.5 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Is there a patch available for CVE-2026-64140?

Yes. CVE-2026-64140 has been patched. Fixed versions include 7.0.11 and 7.1. If you are running Linux kernel 7.0 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-64140 actively exploited?

No. CVE-2026-64140 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.