What is CVE-2026-89771?

CVE-2026-89771 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 6.12.109, 6.18.50, 7.2.4 and others. CVE-2026-89771 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-89771?

CVE-2026-89771 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-2026-89771?

Yes, CVE-2026-89771 has been patched. Fixed versions include 6.12.109, 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-2026-89771 actively exploited?

CVE-2026-89771 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-89771

High

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Fix subbuf resize race with ring buffer readers trace_buffer subbuf_size is read lockless in ring_buffer_read_page() and ring_buffer_read_start(), while it can simultaneously be resized with ring_buffer_subbuf_order_set(). Instead of trace_buffer::subbuf_size, use bpage::order in ring_buffer_read_start() and ring_buffer_read_page(). In ring_buffer_read_start(), even with resize_disabled, there is still a possibility of a race with a buffer modification. Hold the trace_buffer mutex to synchronise with any pending ring buffer order modification. trace_buffer::subbuf_size is now actually useless, remove it. Also, create accessors rb_subbuf_capacity() and rb_page_capacity() which return the actual size available for storing events, while rb_subbuf_size() returns the actual subbuf page-size.

Package Linux Kernel

Published 2026-09-11

Last modified 2026-09-13

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 6.12.109, 6.18.50, 7.2.4, 7.3-rc1 and their respective stable series.

Affected from

≥ 6.8

Fixed in

✓ 6.12.109 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-2026-89771

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2026-09-11

Modified 2026-09-13

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-89771?

CVE-2026-89771 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 6.12.109, 6.18.50, 7.2.4 and others. CVE-2026-89771 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-89771?

CVE-2026-89771 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-2026-89771?

Yes. CVE-2026-89771 has been patched. Fixed versions include 6.12.109, 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-2026-89771 actively exploited?

No. CVE-2026-89771 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.