CVE-2026-89442
Received
Received - Intake
Buffer Overflow in Linux Kernel platform/x86 ISST
Vulnerability report for CVE-2026-89442, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-11
Last updated on: 2026-09-11
Assigner: kernel.org
Description
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().
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |