CVE-2026-25199 (GCVE-0-2026-25199)

Vulnerability from cvelistv5 – Published: 2026-05-08 12:22 – Updated: 2026-05-09 06:43
VLAI
Title
Apache CloudStack: Proxmox Extension Allows Unauthorized Cross-Tenant Instance Access
Summary
Instances deployed via the Proxmox extension allow unauthorized access to instances belonging to other tenants. This issue affects Apache CloudStack: from 4.21.0.0 through 4.22.0.0. The Proxmox extension for CloudStack improperly uses a user-editable instance setting, proxmox_vmid, to associate CloudStack instances with Proxmox virtual machines. Because this value is not restricted or validated against tenant ownership and Proxmox VM IDs are predictable, a non-privileged attacker can modify the setting to reference a VM belonging to another account. This allows unauthorized cross-tenant access and enables full control over the targeted VM, including starting, stopping, and destroying the virtual machine. Users are recommended to upgrade to version 4.22.0.1, which fixes this issue. As a workaround for the existing installations, editing of the proxmox_vmid instance detail by users can be prevented by adding this detail name to the global configuration parameter - user.vm.denied.details.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-08 17:24 UTC
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
Assigner
apache CNA under the mitre root
CNA scorecard B 76/100 over 1112 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache CloudStack Affected: 4.21.0 , ≤ 4.22.0 (semver)
guessed Create a notification for this product.
Credits
Sander Grendelman <sander.grendelman@axians.com>
Show details on NVD website
To clipboard 

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