Skip to content
Fencer Vulns
low 3.8

CVE-2024-31144 json

Xapi: Metadata injection attack against backup/restore functionality

published 2025-02-14 20 mo ago modified 2026-06-17 4 mo ago also EUVD-2024-29054

cvss
3.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 11%
public exploits
0
none known

Summary

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.

Patch / fix

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
20 mo ago

Exploit prediction

0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 3.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
CNA 3.1 3.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N

Affected products

  • Xen Project Xen

Classification

Weakness
  • CWE-829 Inclusion of Functionality from Untrusted Control Sphere

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.