CVE-2026-81011

Description

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.

Gravité et risque d'exploitation

CVE-2026-81011 obtient un score CVSS de 7.1/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.13 %, ce qui la place devant 2.0 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.12.*, 0, 7.2.4, <6.6, <a38127df99ae8b1851560b35b837c9952416143a, <=6.6.*, 6.6.157, <e0ddfd77c0c320b7d12b6c9169303b140b798775, 6.6, <467e53f231f77a1677191b8cdabdaf1448439d55, <=6.18.*, <=7.2.*, <400cbc3ccc88a5ad37cd85056224635ce9eba018, <=*, <436017808c7cbcdb5e49b2142090d4391e3de9a6, a34fc329b1895fc8a6eb12099adc47009421ba6a, 6.18.50, 6.12.109, 7.3) est présent sur votre parc.
• Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
• À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
• Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.

Références

• https://git.kernel.org/stable/c/467e53f231f77a1677191b8cdabdaf1448439d55
• https://git.kernel.org/stable/c/436017808c7cbcdb5e49b2142090d4391e3de9a6
• https://git.kernel.org/stable/c/a38127df99ae8b1851560b35b837c9952416143a
• https://git.kernel.org/stable/c/400cbc3ccc88a5ad37cd85056224635ce9eba018
• https://git.kernel.org/stable/c/e0ddfd77c0c320b7d12b6c9169303b140b798775