What is CVE-2026-99030?

CVE-2026-99030 is a High severity Linux kernel vulnerability with a CVSS score of 7.5 out of 10, affecting Linux kernel versions from 6.12 onward and patched in 6.12.113, 6.18.57, 7.2.11 and others. CVE-2026-99030 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-99030?

CVE-2026-99030 has a CVSS score of 7.5 out of 10, rated High severity. The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Is there a patch available for CVE-2026-99030?

Yes, CVE-2026-99030 has been patched. Fixed versions include 6.12.113, 6.18.57, 7.2.11 and others. If you are running Linux kernel 6.12 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-99030 actively exploited?

CVE-2026-99030 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-99030

High

In the Linux kernel, the following vulnerability has been resolved: net: skbuff: don't leave stale bytes in skb_copy_and_csum_bits() When skb_copy_and_csum_bits() reaches unreadable frags it returns 0 after copying only the linear part, and the rest of the caller's buffer is left as it was. The callers copy into a buffer that is about to go out on the wire: an ICMP error quoting the offending packet, or a driver's TX bounce buffer in skb_copy_and_csum_dev(). Neither buffer is zeroed beforehand, so whatever was in memory there gets sent. Zero the part of the buffer we didn't fill. The checksum usually won't match the data any more, so the receiver will usually drop the packet, but either way it no longer carries anything it shouldn't. Only zero for a positive @len, a negative one from a broken caller must not turn into a huge memset().

Package Linux Kernel

Published 2026-10-23

Last modified 2026-10-24

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.5

out of 10

High

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Vector string

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

Affected versions

Linux kernel versions 6.12 and later are affected. Fixed in 6.12.113, 6.18.57, 7.2.11, 7.3 and their respective stable series.

Affected from

≥ 6.12

Fixed in

✓ 6.12.113 6.12.x ✓ 6.18.57 6.18.x ✓ 7.2.11 7.2.x ✓ 7.3

References

4 total

Details

CVE ID CVE-2026-99030

Severity High

CVSS score 7.5 / 10

CVSS version 3.1

Published 2026-10-23

Modified 2026-10-24

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-99030?

CVE-2026-99030 is a High severity Linux kernel vulnerability with a CVSS score of 7.5 out of 10 . It affects Linux kernel versions from 6.12 onward and has been patched in 6.12.113, 6.18.57, 7.2.11 and others. CVE-2026-99030 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-99030?

CVE-2026-99030 has a CVSS score of 7.5 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
Is there a patch available for CVE-2026-99030?

Yes. CVE-2026-99030 has been patched. Fixed versions include 6.12.113, 6.18.57, 7.2.11 and others. If you are running Linux kernel 6.12 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-99030 actively exploited?

No. CVE-2026-99030 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.