What is CVE-2026-89503?

CVE-2026-89503 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, affecting Linux kernel versions from 6.8 onward and patched in 6.12.112, 6.18.50, 7.2.4 and others. CVE-2026-89503 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-89503?

CVE-2026-89503 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-89503?

Yes, CVE-2026-89503 has been patched. Fixed versions include 6.12.112, 6.18.50, 7.2.4 and others. If you are running Linux kernel 6.8 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-89503 actively exploited?

CVE-2026-89503 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-89503

High

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Fix subbuf resize race with ring_buffer_alloc_read_page() ring_buffer_alloc_read_page() is racy with ring_buffer_subbuf_order_set, it can allocate a reader page with an outdated order. This isn't a big issue, the user can still re-allocate a new reader page and try again. However, what is more problematic is if the value of subbuf_order changes in the middle of ring_buffer_alloc_read_page(). In that case, bpage->order might not match the actual allocated memory. Use bpage->order for the allocation to prevent this race.

Package Linux Kernel

Published 2026-09-11

Last modified 2026-10-03

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Affected versions

Linux kernel versions 6.8 and later are affected. Fixed in 6.12.112, 6.18.50, 7.2.4, 7.3-rc1 and their respective stable series.

Affected from

≥ 6.8

Fixed in

✓ 6.12.112 6.12.x ✓ 6.18.50 6.18.x ✓ 7.2.4 7.2.x ✓ 7.3-rc1

References

4 total

Details

CVE ID CVE-2026-89503

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2026-09-11

Modified 2026-10-03

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-89503?

CVE-2026-89503 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 6.8 onward and has been patched in 6.12.112, 6.18.50, 7.2.4 and others. CVE-2026-89503 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-89503?

CVE-2026-89503 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-89503?

Yes. CVE-2026-89503 has been patched. Fixed versions include 6.12.112, 6.18.50, 7.2.4 and others. If you are running Linux kernel 6.8 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-89503 actively exploited?

No. CVE-2026-89503 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.