Heimdall Security Logo

CVE-2026-46132

Vulnérabilité non évaluée dans Linux (Linux)

CVSS 0.0 · Non évaluée
EPSS 0.2%
Linux•Linux•Versions : <=6.1.*, 7.0.7, <=7.0.*, <=6.12.*, <fbe0e6197225e6a83cf113a67a4b425f8de0bcd5, 0, <38bcc21f52246badb3154b6158dcb381d98de011, 6.12.88, <a44fbb631cba646532f3948636626f81717365a7, <14271b401ec6a4bf0d88054106fc2956084717e1, 5.15.209, <cccce3190ba4356432b9f22369b56123d3d89f0d, <=5.10.*, <=6.6.*, 6.1.175, <c5b1b92ab7eff1a6e8c507ddde6fd02fabd0cfa8, 5.3, 7.1, <=6.18.*, <5.3, 5.10.258, 75345f888f700c4ab2448287e35d48c760b202e6, <=*, <0653c0516234c8258975d268a749115fc0f0ff00, <=5.15.*, <4b9e327991815e128ad3af75c3a04630a63ce3e0, 6.6.140, 6.18.30

Description

In the Linux kernel, the following vulnerability has been resolved: net: rtnetlink: zero ifla_vf_broadcast to avoid stack infoleak in rtnl_fill_vfinfo rtnl_fill_vfinfo() declares struct ifla_vf_broadcast on the stack without initialisation: struct ifla_vf_broadcast vf_broadcast; The struct contains a single fixed 32-byte field: /* include/uapi/linux/if_link.h */ struct ifla_vf_broadcast { __u8 broadcast[32]; }; The function then copies dev->broadcast into it using dev->addr_len as the length: memcpy(vf_broadcast.broadcast, dev->broadcast, dev->addr_len); On Ethernet devices (the overwhelming majority of SR-IOV NICs) dev->addr_len is 6, so only the first 6 bytes of broadcast[] are written. The remaining 26 bytes retain whatever was previously on the kernel stack. The full struct is then handed to userspace via: nla_put(skb, IFLA_VF_BROADCAST, sizeof(vf_broadcast), &vf_broadcast) leaking up to 26 bytes of uninitialised kernel stack per VF per RTM_GETLINK request, repeatable. The other vf_* structs in the same function are explicitly zeroed for exactly this reason - see the memset() calls for ivi, vf_vlan_info, node_guid and port_guid a few lines above. vf_broadcast was simply missed when it was added. Reachability: any unprivileged local process can open AF_NETLINK / NETLINK_ROUTE without capabilities and send RTM_GETLINK with an IFLA_EXT_MASK attribute carrying RTEXT_FILTER_VF. The kernel walks each VF and emits IFLA_VF_BROADCAST, leaking 26 bytes of stack per VF per request. Stack residue at this call site can include return addresses and transient sensitive data; KASAN with stack instrumentation, or KMSAN, will flag the nla_put() when reproduced. Zero the on-stack struct before the partial memcpy, matching the existing pattern used for the other vf_* structs in the same function.

Gravité et risque d'exploitation

CVE-2026-46132 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 0.17 %, ce qui la place devant 6.1 % des CVE référencées.

Que faire ?

  • Vérifiez si Linux (versions <=6.1.*, 7.0.7, <=7.0.*, <=6.12.*, <fbe0e6197225e6a83cf113a67a4b425f8de0bcd5, 0, <38bcc21f52246badb3154b6158dcb381d98de011, 6.12.88, <a44fbb631cba646532f3948636626f81717365a7, <14271b401ec6a4bf0d88054106fc2956084717e1, 5.15.209, <cccce3190ba4356432b9f22369b56123d3d89f0d, <=5.10.*, <=6.6.*, 6.1.175, <c5b1b92ab7eff1a6e8c507ddde6fd02fabd0cfa8, 5.3, 7.1, <=6.18.*, <5.3, 5.10.258, 75345f888f700c4ab2448287e35d48c760b202e6, <=*, <0653c0516234c8258975d268a749115fc0f0ff00, <=5.15.*, <4b9e327991815e128ad3af75c3a04630a63ce3e0, 6.6.140, 6.18.30) 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

Rechercher une autre CVE