Fiche vulnérabilité

CVE-2026-45890 : faille moyenne linux linux kernel (CVSS 5.5)

Description

In the Linux kernel, the following vulnerability has been resolved: xen-netback: reject zero-queue configuration from guest A malicious or buggy Xen guest can write "0" to the xenbus key "multi-queue-num-queues". The connect() function in the backend only validates the upper bound (requested_num_queues > xenvif_max_queues) but not zero, allowing requested_num_queues=0 to reach vzalloc(array_size(0, sizeof(struct xenvif_queue))), which triggers WARN_ON_ONCE(!size) in __vmalloc_node_range(). On systems with panic_on_warn=1, this allows a guest-to-host denial of service. The Xen network interface specification requires the queue count to be "greater than zero". Add a zero check to match the validation already present in xen-blkback, which has included this guard since its multi-queue support was added.

En bref

Sévérité: Moyenne (CVSS 5.5)
Vecteur CVSS: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Exploitation active: Non signalée par la CISA
Publication: 27 mai 2026
Dernière mise à jour: 25 juin 2026

Produits concernés

linux linux kernel

Références

Rechercher une autre vulnérabilité dans la base CVE