CVE-2026-81011

Status: UPDATED  |  Advisory ID: CVE-2026-81011

Key Details

Affected Products, Subsystems & Sectors

What to Know

In the Linux kernel, the following vulnerability has been resolved:

platform/x86: hp-bioscfg: pass validated element count to package parsers

The per-type package parsers are handed the wrong element count.

hp_init_bios_package_attribute() validates obj->package.count and then

calls one of the five hp_populate_*_package_data() wrappers (string,

integer, enumeration, ordered list, password). Each wrapper forwards a

count to its hp_populate_*_elements_from_package() parser, but instead

of forwarding the validated obj->package.count it derives the count

from elements[0]. elements[0] is the NAME field and is always an

ACPI_TYPE_STRING, so reading ->package.count from it in fact reads

->string.length through the union acpi_object. The parsers thus bound

themselves against the length of the name string rather than against

the real number of elements in the package.

This is safe today because hp_init_bios_package_attribute() refuses any

package that has fewer than the type's element count, so a parser only

ever runs on a full package and never reads past it regardless of the

bogus bound.

An upcoming change relaxes that check to accept shorter packages. Once

a parser can receive fewer elements than its per-type count, a bound

taken from the name length no longer reflects the array size, and the

"elem < count" loop conditions and "elem + n >= count" sub-loop guards

read past the end of elements[] - an out-of-bounds heap read.

Forward the validated obj->package.count to every *_package_data()

wrapper so the parsers bound themselves against the real package size.

This does not change behaviour for the packages that enumerate

correctly today and is a prerequisite for accepting shorter packages

safely. (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References