What is CVE-2026-43377?

CVE-2026-43377 is a High severity Linux kernel vulnerability with a CVSS score of 8.1 out of 10, affecting Linux kernel versions from 5.15 onward and patched in 6.1.167, 6.6.130, 6.12.78 and others. CVE-2026-43377 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-43377?

CVE-2026-43377 has a CVSS score of 8.1 out of 10, rated High severity. The vector string is CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.

Is there a patch available for CVE-2026-43377?

Yes, CVE-2026-43377 has been patched. Fixed versions include 6.1.167, 6.6.130, 6.12.78 and others. If you are running Linux kernel 5.15 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-43377 actively exploited?

CVE-2026-43377 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-43377

High

In the Linux kernel, the following vulnerability has been resolved: ksmbd: Don't log keys in SMB3 signing and encryption key generation When KSMBD_DEBUG_AUTH logging is enabled, generate_smb3signingkey() and generate_smb3encryptionkey() log the session, signing, encryption, and decryption key bytes. Remove the logs to avoid exposing credentials.

Package Linux Kernel

Published 2026-05-08

Last modified 2026-05-15

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

8.1

out of 10

High

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

Vector string

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

Affected versions

Linux kernel versions 5.15 and later are affected. Fixed in 6.1.167, 6.6.130, 6.12.78, 6.18.20, 6.19.9, 7.0 and their respective stable series.

Affected from

≥ 5.15

Fixed in

✓ 6.1.167 6.1.x ✓ 6.6.130 6.6.x ✓ 6.12.78 6.12.x ✓ 6.18.20 6.18.x ✓ 6.19.9 6.19.x ✓ 7.0

References

The following references provide additional information about CVE-2026-43377 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Kernel patch commit
https://git.kernel.org/stable/c/3fe2d9ec166b7df9a8df6c0fdcfc210572e27e3f
Patch
Kernel patch commit
https://git.kernel.org/stable/c/407cc37c21d51f9b9d4d20204b04890880cfa6ae
Patch
Kernel patch commit
https://git.kernel.org/stable/c/4084ed720d7d5f4e975c9e4a6267a552dad3b24a
Patch

6 patch commits total View all on NVD

Details

CVE ID CVE-2026-43377

Severity High

CVSS score 8.1 / 10

CVSS version 3.1

Published 2026-05-08

Modified 2026-05-15

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-43377?

CVE-2026-43377 is a High severity Linux kernel vulnerability with a CVSS score of 8.1 out of 10 . It affects Linux kernel versions from 5.15 onward and has been patched in 6.1.167, 6.6.130, 6.12.78 and others. CVE-2026-43377 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-43377?

CVE-2026-43377 has a CVSS score of 8.1 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.
Is there a patch available for CVE-2026-43377?

Yes — CVE-2026-43377 has been patched. Fixed versions include 6.1.167, 6.6.130, 6.12.78 and others. If you are running Linux kernel 5.15 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-43377 actively exploited?

No — CVE-2026-43377 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.