What is CVE-2026-63830?

CVE-2026-63830 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.4 out of 10, affecting Linux kernel versions from 4.20 onward and patched in 5.10.261, 5.15.212, 6.1.177 and others. CVE-2026-63830 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-63830?

CVE-2026-63830 has a CVSS score of 9.4 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:L.

Is there a patch available for CVE-2026-63830?

Yes, CVE-2026-63830 has been patched. Fixed versions include 5.10.261, 5.15.212, 6.1.177 and others. If you are running Linux kernel 4.20 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-63830 actively exploited?

CVE-2026-63830 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-63830

Critical

In the Linux kernel, the following vulnerability has been resolved: net: skmsg: preserve sg.copy across SG transforms The sk_msg sg.copy bitmap is part of the scatterlist entry ownership state. A set bit tells sk_msg_compute_data_pointers() not to expose the entry through writable BPF ctx->data. This protects entries backed by pages that are not private to the sk_msg, such as splice-backed file page-cache pages. Several sk_msg transform paths move, copy, split, or compact msg->sg.data[] entries without moving the matching sg.copy bit. This can make an externally backed entry arrive at a new slot with a clear copy bit. A later SK_MSG verdict can then expose sg_virt(sge) as writable ctx->data and BPF stores can modify the original page cache. Keep sg.copy synchronized with sg.data[] whenever entries are transferred, shifted, split, or copied into a new sk_msg. Clear the bit when an entry is replaced by a newly allocated private page or freed. This covers the BPF pull/push/pop helpers, sk_msg_shift_left/right(), sk_msg_xfer(), and tls_split_open_record(), including the partial tail entry created during TLS open-record splitting.

Package Linux Kernel

Published 2026-07-19

Last modified 2026-08-17

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

9.4

out of 10

Critical

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

Low

Vector string

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

Affected versions

Linux kernel versions 4.20 and later are affected. Fixed in 5.10.261, 5.15.212, 6.1.177, 6.6.144, 6.12.95, 6.18.38, 7.1.3, 7.2 and their respective stable series.

Affected from

≥ 4.20

Fixed in

✓ 5.10.261 5.10.x ✓ 5.15.212 5.15.x ✓ 6.1.177 6.1.x ✓ 6.6.144 6.6.x ✓ 6.12.95 6.12.x ✓ 6.18.38 6.18.x ✓ 7.1.3 7.1.x ✓ 7.2

References

8 total

Showing 5 of 8 references View all on NVD

Details

CVE ID CVE-2026-63830

Severity Critical

CVSS score 9.4 / 10

CVSS version 3.1

Published 2026-07-19

Modified 2026-08-17

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-63830?

CVE-2026-63830 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.4 out of 10 . It affects Linux kernel versions from 4.20 onward and has been patched in 5.10.261, 5.15.212, 6.1.177 and others. CVE-2026-63830 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-63830?

CVE-2026-63830 has a CVSS score of 9.4 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:L.
Is there a patch available for CVE-2026-63830?

Yes. CVE-2026-63830 has been patched. Fixed versions include 5.10.261, 5.15.212, 6.1.177 and others. If you are running Linux kernel 4.20 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-63830 actively exploited?

No. CVE-2026-63830 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.