CVE-2024-31144
Vulnérabilité faible dans Xen (Xen Project)
Description
For a brief summary of Xapi terminology, see: https://xapi-project.github.io/xen-api/overview.html#object-model-overview Xapi contains functionality to backup and restore metadata about Virtual Machines and Storage Repositories (SRs). The metadata itself is stored in a Virtual Disk Image (VDI) inside an SR. This is used for two purposes; a general backup of metadata (e.g. to recover from a host failure if the filer is still good), and Portable SRs (e.g. using an external hard drive to move VMs to another host). Metadata is only restored as an explicit administrator action, but occurs in cases where the host has no information about the SR, and must locate the metadata VDI in order to retrieve the metadata. The metadata VDI is located by searching (in UUID alphanumeric order) each VDI, mounting it, and seeing if there is a suitable metadata file present. The first matching VDI is deemed to be the metadata VDI, and is restored from. In the general case, the content of VDIs are controlled by the VM owner, and should not be trusted by the host administrator. A malicious guest can manipulate its disk to appear to be a metadata backup. A guest cannot choose the UUIDs of its VDIs, but a guest with one disk has a 50% chance of sorting ahead of the legitimate metadata backup. A guest with two disks has a 75% chance, etc.
Gravité et risque d'exploitation
CVE-2024-31144 obtient un score CVSS de 3.8/10, soit une gravité faible. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.21 %, ce qui la place devant 11.2 % des CVE référencées.
Que faire ?
- Vérifiez si Xen (versions consult Xen advisory XSA-459) 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.