Vulnerability Description
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.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Apache | Cloudstack | >= 4.21.0.0, < 4.22.0.1 |
Related Weaknesses (CWE)
References
- https://lists.apache.org/thread/n8mt5b7wkpysstb8w7rr9f02kc5cq2xmMailing ListVendor Advisory
- http://www.openwall.com/lists/oss-security/2026/05/09/7
FAQ
What is CVE-2026-25199?
CVE-2026-25199 is a vulnerability with a CVSS score of 9.1 (CRITICAL). 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 Proxmo...
How severe is CVE-2026-25199?
CVE-2026-25199 has been rated CRITICAL with a CVSS base score of 9.1/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-25199?
Check the references section above for vendor advisories and patch information. Affected products include: Apache Cloudstack.