What is CVE-2026-80637?

CVE-2026-80637 is a High severity Linux kernel vulnerability with a CVSS score of 7.5 out of 10, affecting Linux kernel versions from 3.12 onward and patched in 6.12.97, 6.18.40, 7.1.5 and others. CVE-2026-80637 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-80637?

CVE-2026-80637 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:N/I:N/A:H.

Is there a patch available for CVE-2026-80637?

Yes, CVE-2026-80637 has been patched. Fixed versions include 6.12.97, 6.18.40, 7.1.5 and others. If you are running Linux kernel 3.12 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-80637 actively exploited?

CVE-2026-80637 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-80637

High

In the Linux kernel, the following vulnerability has been resolved: netfilter: synproxy: fix unaligned memory access in timestamp adjustment Use get_unaligned_be32() and put_unaligned_be32() to safely read and write the timestamp fields. This prevents performance degradation due to unaligned memory access or even a crash on strict alignment architectures. This follows the implementation of timestamp parsing in the networking stack at tcp_parse_options() and synproxy_parse_options().

Package Linux Kernel

Published 2026-08-28

Last modified 2026-08-29

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

Low

Integrity

None

Availability

High

Vector string

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

Affected versions

Linux kernel versions 3.12 and later are affected. Fixed in 6.12.97, 6.18.40, 7.1.5, 7.2 and their respective stable series.

Affected from

≥ 3.12

Fixed in

✓ 6.12.97 6.12.x ✓ 6.18.40 6.18.x ✓ 7.1.5 7.1.x ✓ 7.2

References

4 total

Details

CVE ID CVE-2026-80637

Severity High

CVSS score 7.5 / 10

CVSS version 3.1

Published 2026-08-28

Modified 2026-08-29

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-80637?

CVE-2026-80637 is a High severity Linux kernel vulnerability with a CVSS score of 7.5 out of 10 . It affects Linux kernel versions from 3.12 onward and has been patched in 6.12.97, 6.18.40, 7.1.5 and others. CVE-2026-80637 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-80637?

CVE-2026-80637 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:N/I:N/A:H.
Is there a patch available for CVE-2026-80637?

Yes. CVE-2026-80637 has been patched. Fixed versions include 6.12.97, 6.18.40, 7.1.5 and others. If you are running Linux kernel 3.12 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-80637 actively exploited?

No. CVE-2026-80637 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.