What is CVE-2026-98239?

CVE-2026-98239 is a High severity Linux kernel vulnerability with a CVSS score of 8.1 out of 10, affecting Linux kernel versions from 6.1 onward and patched in 6.1.189, 6.6.158, 6.12.112 and others. CVE-2026-98239 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-98239?

CVE-2026-98239 has a CVSS score of 8.1 out of 10, rated High severity. The vector string is CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-98239?

Yes, CVE-2026-98239 has been patched. Fixed versions include 6.1.189, 6.6.158, 6.12.112 and others. If you are running Linux kernel 6.1 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-98239 actively exploited?

CVE-2026-98239 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-98239

High

In the Linux kernel, the following vulnerability has been resolved: net: lan743x: fix RX checksum use-after-free lan743x_rx_process_buffer() adds each non-first receive buffer to the head skb's frag_list. On the last descriptor, lan743x_rx_trim_skb() linearizes the head and frees the fragment skb metadata. The checksum-success path then writes ip_summed through the local skb pointer, which still points to the final fragment. This causes a use-after-free write when a packet spans more than one receive buffer. Set ip_summed on the surviving head skb instead. Multi-buffer receive can occur after a live MTU increase because existing ring entries keep their old buffer size until they are replenished. A KUnit test invoking lan743x_rx_process_buffer() with a two-buffer packet produced a one-byte KASAN use-after-free write before this change. The same test passed after the change. The driver object also builds with W=1. This was not tested on physical LAN743x hardware.

Package Linux Kernel

Published 2026-10-06

Last modified 2026-10-07

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

8.1

out of 10

High

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Affected versions

Linux kernel versions 6.1 and later are affected. Fixed in 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8, 7.3-rc4 and their respective stable series.

Affected from

≥ 6.1

Fixed in

✓ 6.1.189 6.1.x ✓ 6.6.158 6.6.x ✓ 6.12.112 6.12.x ✓ 6.18.54 6.18.x ✓ 7.2.8 7.2.x ✓ 7.3-rc4

References

6 total

Showing 5 of 6 references View all on NVD

Details

CVE ID CVE-2026-98239

Severity High

CVSS score 8.1 / 10

CVSS version 3.1

Published 2026-10-06

Modified 2026-10-07

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-98239?

CVE-2026-98239 is a High severity Linux kernel vulnerability with a CVSS score of 8.1 out of 10 . It affects Linux kernel versions from 6.1 onward and has been patched in 6.1.189, 6.6.158, 6.12.112 and others. CVE-2026-98239 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-98239?

CVE-2026-98239 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:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-98239?

Yes. CVE-2026-98239 has been patched. Fixed versions include 6.1.189, 6.6.158, 6.12.112 and others. If you are running Linux kernel 6.1 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-98239 actively exploited?

No. CVE-2026-98239 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.