What is CVE-2026-68123?

CVE-2026-68123 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.8 out of 10, affecting Linux kernel versions from 4.8 onward and patched in 5.10.265, 5.15.216, 6.1.183 and others. CVE-2026-68123 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-68123?

CVE-2026-68123 has a CVSS score of 9.8 out of 10, rated Critical severity. The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-68123?

Yes, CVE-2026-68123 has been patched. Fixed versions include 5.10.265, 5.15.216, 6.1.183 and others. If you are running Linux kernel 4.8 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-68123 actively exploited?

CVE-2026-68123 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-68123

Critical

In the Linux kernel, the following vulnerability has been resolved: openvswitch: fix GSO userspace truncation underflow OVS_ACTION_ATTR_TRUNC currently stores a delta from the original skb length in OVS_CB(skb)->cutlen. When a later userspace action segments a GSO skb, queue_gso_packets() reuses that delta for each smaller segment. A segment can then reach queue_userspace_packet() with cutlen greater than skb->len, underflowing the length passed to skb_zerocopy(). Store the maximum preserved length instead and bound each consumer against the current skb length. Use U32_MAX as the no-truncation sentinel so the value remains valid if skb geometry changes before a consumer handles it.

Package Linux Kernel

Published 2026-08-10

Last modified 2026-08-19

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

9.8

out of 10

Critical

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Affected versions

Linux kernel versions 4.8 and later are affected. Fixed in 5.10.265, 5.15.216, 6.1.183, 6.6.148, 6.12.101, 6.18.42, 7.1.6, 7.2 and their respective stable series.

Affected from

≥ 4.8

Fixed in

✓ 5.10.265 5.10.x ✓ 5.15.216 5.15.x ✓ 6.1.183 6.1.x ✓ 6.6.148 6.6.x ✓ 6.12.101 6.12.x ✓ 6.18.42 6.18.x ✓ 7.1.6 7.1.x ✓ 7.2

References

8 total

Showing 5 of 8 references View all on NVD

Details

CVE ID CVE-2026-68123

Severity Critical

CVSS score 9.8 / 10

CVSS version 3.1

Published 2026-08-10

Modified 2026-08-19

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-68123?

CVE-2026-68123 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.8 out of 10 . It affects Linux kernel versions from 4.8 onward and has been patched in 5.10.265, 5.15.216, 6.1.183 and others. CVE-2026-68123 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-68123?

CVE-2026-68123 has a CVSS score of 9.8 out of 10, rated Critical severity (CVSS 3.1). The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-68123?

Yes. CVE-2026-68123 has been patched. Fixed versions include 5.10.265, 5.15.216, 6.1.183 and others. If you are running Linux kernel 4.8 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-68123 actively exploited?

No. CVE-2026-68123 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.