What is CVE-2026-43084?

CVE-2026-43084 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, classified as a Use After Free flaw (CWE-416), affecting Linux kernel versions from 6.12.75 onward and patched in 6.12.83, 6.18.24 and 6.19.14. CVE-2026-43084 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-43084?

CVE-2026-43084 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-43084?

Yes, CVE-2026-43084 has been patched. Fixed versions include 6.12.83, 6.18.24 and 6.19.14. If you are running Linux kernel 6.12.75 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-43084 actively exploited?

CVE-2026-43084 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Use After Free (CWE-416)?

The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/416.html

CVE-2026-43084

High

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue: make hash table per queue Sharing a global hash table among all queues is tempting, but it can cause crash: BUG: KASAN: slab-use-after-free in nfqnl_recv_verdict+0x11ac/0x15e0 [nfnetlink_queue] [..] nfqnl_recv_verdict+0x11ac/0x15e0 [nfnetlink_queue] nfnetlink_rcv_msg+0x46a/0x930 kmem_cache_alloc_node_noprof+0x11e/0x450 struct nf_queue_entry is freed via kfree, but parallel cpu can still encounter such an nf_queue_entry when walking the list. Alternative fix is to free the nf_queue_entry via kfree_rcu() instead, but as we have to alloc/free for each skb this will cause more mem pressure.

Package Linux Kernel

Published 2026-05-06

Last modified 2026-06-05

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Weakness type

CWE-416

CVE-2026-43084 is a Use After Free vulnerability

What is Use After Free?

The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. Learn more on MITRE CWE

Affected versions

Linux kernel versions 6.12.75, 6.18.14, 6.19.4 and later are affected. Fixed in 6.12.83, 6.18.24, 6.19.14 and their respective stable series.

Affected from

≥ 6.12.75 ≥ 6.18.14 ≥ 6.19.4

Fixed in

✓ 6.12.83 6.12.x ✓ 6.18.24 6.18.x ✓ 6.19.14 6.19.x

References

4 total

Kernel Git
https://git.kernel.org/stable/c/22730cb96093b5be0609063bbb1923dbecd61252

Patch
Kernel Git
https://git.kernel.org/stable/c/41e3652a178cb0eecd48e0e6e27fbb73a004046a

Patch
Kernel Git
https://git.kernel.org/stable/c/936206e3f6ff411581e615e930263d6f8b78df9d

Patch
Kernel Git
https://git.kernel.org/stable/c/9e5ebef91120d2764aefe557c3a484b6288f341f

Patch

Details

CVE ID CVE-2026-43084

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2026-05-06

Modified 2026-06-05

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-43084?

CVE-2026-43084 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 6.12.75 onward and has been patched in 6.12.83, 6.18.24 and 6.19.14. CVE-2026-43084 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-43084?

CVE-2026-43084 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-43084?

Yes. CVE-2026-43084 has been patched. Fixed versions include 6.12.83, 6.18.24 and 6.19.14. If you are running Linux kernel 6.12.75 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-43084 actively exploited?

No. CVE-2026-43084 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.