What is CVE-2026-89443?

CVE-2026-89443 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10, affecting Linux kernel versions from 6.4 onward and patched in 6.6.157, 6.12.109, 6.18.50 and others. CVE-2026-89443 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-89443?

CVE-2026-89443 has a CVSS score of 7.1 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:N/A:H.

Is there a patch available for CVE-2026-89443?

Yes, CVE-2026-89443 has been patched. Fixed versions include 6.6.157, 6.12.109, 6.18.50 and others. If you are running Linux kernel 6.4 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-89443 actively exploited?

CVE-2026-89443 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-89443

High

In the Linux kernel, the following vulnerability has been resolved: platform/x86: ISST: Validate level in perf mask ioctls isst_if_get_perf_level_mask() and isst_if_get_base_freq_mask() use the user-provided level as an index into perf_levels[] via _read_pp_level_info() and _read_bf_level_info(), but neither helper validates it first. The adjacent level-info helpers reject levels above max_level before reading the same per-level register block. Add the same bounds checks to the mask helpers, and reject disabled SST-PP levels in isst_if_get_perf_level_mask() to match isst_if_get_perf_level_info(). This prevents out-of-bounds reads from the per-level offset table on invalid ioctl input.

Package Linux Kernel

Published 2026-09-11

Last modified 2026-09-14

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.1

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Vector string

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

Affected versions

Linux kernel versions 6.4 and later are affected. Fixed in 6.6.157, 6.12.109, 6.18.50, 7.2.4, 7.3-rc1 and their respective stable series.

Affected from

≥ 6.4

Fixed in

✓ 6.6.157 6.6.x ✓ 6.12.109 6.12.x ✓ 6.18.50 6.18.x ✓ 7.2.4 7.2.x ✓ 7.3-rc1

References

5 total

Details

CVE ID CVE-2026-89443

Severity High

CVSS score 7.1 / 10

CVSS version 3.1

Published 2026-09-11

Modified 2026-09-14

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-89443?

CVE-2026-89443 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10 . It affects Linux kernel versions from 6.4 onward and has been patched in 6.6.157, 6.12.109, 6.18.50 and others. CVE-2026-89443 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-89443?

CVE-2026-89443 has a CVSS score of 7.1 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:N/A:H.
Is there a patch available for CVE-2026-89443?

Yes. CVE-2026-89443 has been patched. Fixed versions include 6.6.157, 6.12.109, 6.18.50 and others. If you are running Linux kernel 6.4 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-89443 actively exploited?

No. CVE-2026-89443 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.