What is CVE-2026-64040?

CVE-2026-64040 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, affecting Linux kernel versions from 6.15 onward and patched in 6.18.57, 7.0.11 and 7.1. CVE-2026-64040 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-64040?

CVE-2026-64040 has a CVSS score of 5.5 out of 10, rated Medium severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Is there a patch available for CVE-2026-64040?

Yes, CVE-2026-64040 has been patched. Fixed versions include 6.18.57, 7.0.11 and 7.1. If you are running Linux kernel 6.15 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-64040 actively exploited?

CVE-2026-64040 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-64040

Medium

In the Linux kernel, the following vulnerability has been resolved: cachefiles: Fix error return when vfs_mkdir() fails When vfs_mkdir() fails, the error code is not extracted from the returned error pointer. This causes mkdir_error to be reached with ret=0, which leads to returning ERR_PTR(0) (NULL) instead of a proper error pointer. Fix this by extracting the error code from the error pointer when vfs_mkdir() fails.

Package Linux Kernel

Published 2026-07-19

Last modified 2026-10-15

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

5.5

out of 10

Medium

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Vector string

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

Weakness type

CWE-252

CVE-2026-64040 is classified as CWE-252

See CWE-252 on MITRE CWE for full details on this weakness type.

Affected versions

Linux kernel versions 6.15 and later are affected. Fixed in 6.18.57, 7.0.11, 7.1 and their respective stable series.

Affected from

≥ 6.15

Fixed in

✓ 6.18.57 6.18.x ✓ 7.0.11 7.0.x ✓ 7.1

References

3 total

Kernel Git
https://git.kernel.org/stable/c/0940108d27c6995e02819ff832be11892f0b208b

Patch
Kernel Git
https://git.kernel.org/stable/c/8a220d1c312c66194f4a33dd52d1fba42bc2b341

Patch
Kernel Git
https://git.kernel.org/stable/c/86f4c1586418d50203ee8d76cba5d7b148719a32

Details

CVE ID CVE-2026-64040

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2026-07-19

Modified 2026-10-15

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-64040?

CVE-2026-64040 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 6.15 onward and has been patched in 6.18.57, 7.0.11 and 7.1. CVE-2026-64040 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-64040?

CVE-2026-64040 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Is there a patch available for CVE-2026-64040?

Yes. CVE-2026-64040 has been patched. Fixed versions include 6.18.57, 7.0.11 and 7.1. If you are running Linux kernel 6.15 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-64040 actively exploited?

No. CVE-2026-64040 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.