What is CVE-2026-43333?

CVE-2026-43333 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, classified as a NULL Pointer Dereference flaw (CWE-476), affecting Linux kernel versions from 5.15.37 onward and patched in 5.15.203, 6.1.168, 6.6.134 and others. CVE-2026-43333 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-43333?

CVE-2026-43333 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-2026-43333?

Yes, CVE-2026-43333 has been patched. Fixed versions include 5.15.203, 6.1.168, 6.6.134 and others. If you are running Linux kernel 5.15.37 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-43333 actively exploited?

CVE-2026-43333 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-2026-43333

Medium

In the Linux kernel, the following vulnerability has been resolved: bpf: reject direct access to nullable PTR_TO_BUF pointers check_mem_access() matches PTR_TO_BUF via base_type() which strips PTR_MAYBE_NULL, allowing direct dereference without a null check. Map iterator ctx->key and ctx->value are PTR_TO_BUF | PTR_MAYBE_NULL. On stop callbacks these are NULL, causing a kernel NULL dereference. Add a type_may_be_null() guard to the PTR_TO_BUF branch, matching the existing PTR_TO_BTF_ID pattern.

Package Linux Kernel

Published 2026-05-08

Last modified 2026-05-15

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-476

CVE-2026-43333 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 5.15.37, 5.16.11, 5.17 and later are affected. Fixed in 5.15.203, 6.1.168, 6.6.134, 6.12.81, 6.18.22, 6.19.12, 7.0 and their respective stable series.

Affected from

≥ 5.15.37 ≥ 5.16.11 ≥ 5.17

Fixed in

✓ 5.15.203 5.15.x ✓ 6.1.168 6.1.x ✓ 6.6.134 6.6.x ✓ 6.12.81 6.12.x ✓ 6.18.22 6.18.x ✓ 6.19.12 6.19.x ✓ 7.0

References

7 total

Kernel Git
https://git.kernel.org/stable/c/10bc4a4dcded509c5d5c67d497900c3922c604cd

Patch
Kernel Git
https://git.kernel.org/stable/c/21a10c06ffae24cb01fd174a7ab7736001d2ea56

Patch
Kernel Git
https://git.kernel.org/stable/c/4f6c99dc0420f1a3d671c1b8ab8a7ac84d9cba09

Patch
Kernel Git
https://git.kernel.org/stable/c/63276547debc4d8a73eefb2c5273b2a905c961b0

Patch
Kernel Git
https://git.kernel.org/stable/c/70abd9d118da2f56beb4ec22e3a29becae373535

Patch

Showing 5 of 7 references View all on NVD

Details

CVE ID CVE-2026-43333

Severity Medium

CVSS score 5.5 / 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-2026-43333?

CVE-2026-43333 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 5.15.37 onward and has been patched in 5.15.203, 6.1.168, 6.6.134 and others. CVE-2026-43333 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-43333?

CVE-2026-43333 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-2026-43333?

Yes. CVE-2026-43333 has been patched. Fixed versions include 5.15.203, 6.1.168, 6.6.134 and others. If you are running Linux kernel 5.15.37 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-43333 actively exploited?

No. CVE-2026-43333 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.