What is CVE-2026-89442?

CVE-2026-89442 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 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-2026-89442 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-89442?

CVE-2026-89442 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-2026-89442?

Yes, CVE-2026-89442 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-2026-89442 actively exploited?

CVE-2026-89442 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-89442

High

In the Linux kernel, the following vulnerability has been resolved: platform/x86: ISST: Validate socket ID in clos_assoc ioctl isst_if_clos_assoc() validates the user-supplied socket_id with 'socket_id > topology_max_packages()', but isst_common.sst_inst[] is allocated with topology_max_packages() entries, so the valid index range is [0, topology_max_packages()). The '>' comparison lets socket_id == topology_max_packages() pass and index one entry past the array. In addition, isst_common.sst_inst[socket_id] is NULL for an in-range package that has no bound TPMI SST instance, and the pointer is used without a NULL check. Both the out-of-bounds entry and the NULL pointer are then dereferenced by map_partition_power_domain_id() and the following power_domain_info access. Reject socket_id >= topology_max_packages() and a NULL sst_inst, matching the checks already performed by get_instance().

Package Linux Kernel

Published 2026-09-11

Last modified 2026-09-14

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 6.4 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-2026-89442

Severity High

CVSS score 7.8 / 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-2026-89442?

CVE-2026-89442 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 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-2026-89442 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-89442?

CVE-2026-89442 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-2026-89442?

Yes. CVE-2026-89442 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-2026-89442 actively exploited?

No. CVE-2026-89442 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.