CVE-2026-23085

Description

In the Linux kernel, the following vulnerability has been resolved: irqchip/gic-v3-its: Avoid truncating memory addresses On 32-bit machines with CONFIG_ARM_LPAE, it is possible for lowmem allocations to be backed by addresses physical memory above the 32-bit address limit, as found while experimenting with larger VMSPLIT configurations. This caused the qemu virt model to crash in the GICv3 driver, which allocates the 'itt' object using GFP_KERNEL. Since all memory below the 4GB physical address limit is in ZONE_DMA in this configuration, kmalloc() defaults to higher addresses for ZONE_NORMAL, and the ITS driver stores the physical address in a 32-bit 'unsigned long' variable. Change the itt_addr variable to the correct phys_addr_t type instead, along with all other variables in this driver that hold a physical address. The gicv5 driver correctly uses u64 variables, while all other irqchip drivers don't call virt_to_phys or similar interfaces. It's expected that other device drivers have similar issues, but fixing this one is sufficient for booting a virtio based guest.

Gravité et risque d'exploitation

CVE-2026-23085 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.14 %, ce qui la place devant 3.3 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.1.*, <=6.12.*, 3.19, 0, 5.15.199, <e332b3b69e5b3acf07204a4b185071bab15c2b88, <85215d633983233809f7d4dad163b953331b8238, <=5.10.*, <=6.6.*, <1b323391560354d8c515de8658b057a1daa82adb, 5.10.249, 6.18.8, <8d76a7d89c12d08382b66e2f21f20d0627d14859, <084ba3b99f2dfd991ce7e84fb17117319ec3cd9f, 6.1.162, <=6.18.*, 6.12.68, <03faa61eb4b9ca9aa09bd91d4c3773d8e7b1ac98, cc2d3216f53c9fff0030eb71cacc4ce5f39d1d7e, <=*, <=5.15.*, 6.19, <3.19, 6.6.122, <e2f9c751f73a2d5bb62d94ab030aec118a811f27) 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/e332b3b69e5b3acf07204a4b185071bab15c2b88
• https://git.kernel.org/stable/c/e2f9c751f73a2d5bb62d94ab030aec118a811f27
• https://git.kernel.org/stable/c/85215d633983233809f7d4dad163b953331b8238
• https://git.kernel.org/stable/c/1b323391560354d8c515de8658b057a1daa82adb
• https://git.kernel.org/stable/c/084ba3b99f2dfd991ce7e84fb17117319ec3cd9f
• https://git.kernel.org/stable/c/03faa61eb4b9ca9aa09bd91d4c3773d8e7b1ac98
• https://git.kernel.org/stable/c/8d76a7d89c12d08382b66e2f21f20d0627d14859