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().
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Sun, 13 Sep 2026 06:45:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 4.1, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Sat, 12 Sep 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-476
References
Metrics threat_severity

None

cvssV3_1

{'score': 4.1, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Fri, 11 Sep 2026 23:45:00 +0000

Type Values Removed Values Added
Description 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().
Title platform/x86: ISST: Validate socket ID in clos_assoc ioctl
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-09-13T06:29:24.643Z

Reserved: 2026-09-11T19:38:34.703Z

Link: CVE-2026-89442

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-11T20:19:24.613

Modified: 2026-09-13T07:17:08.810

Link: CVE-2026-89442

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-09-11T19:43:10Z

Links: CVE-2026-89442 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-09-13T09:00:13Z

Weaknesses