{
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09"
      },
      "title": "Proxmox Extension Allows Unauthorized Cross-Tenant Instance Access",
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-200 Exposure of Sensitive Information to an Unauthorized Actor",
              "lang": "en",
              "cweId": "CWE-200",
              "type": "CWE"
            }
          ]
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "affected": [
        {
          "vendor": "Apache Software Foundation",
          "product": "Apache CloudStack",
          "versions": [
            {
              "status": "affected",
              "version": "4.21.0",
              "lessThanOrEqual": "4.22.0",
              "versionType": "semver"
            }
          ],
          "defaultStatus": "unaffected"
        }
      ],
      "descriptions": [
        {
          "value": "Instances deployed via the Proxmox extension allow unauthorized access to instances belonging to other tenants.\n\n\n\n\nThis issue affects Apache CloudStack: from 4.21.0.0 through 4.22.0.0.\n\n\n\n\nThe 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.\n\n\n\n\nUsers are recommended to upgrade to version 4.22.0.1, which fixes this issue.\n\n\n\n\nAs a workaround for the existing installations,\u00a0editing 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.",
          "lang": "en",
          "supportingMedia": [
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              "value": "<div>Instances deployed via the Proxmox extension allow unauthorized access to instances belonging to other tenants.</div><div><br></div><div>This issue affects Apache CloudStack: from 4.21.0.0 through 4.22.0.0.</div><div><br></div><div>The Proxmox extension for CloudStack improperly uses a user-editable instance setting, <code>proxmox_vmid</code>, 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.</div><div><br></div><div>Users are recommended to upgrade to version 4.22.0.1, which fixes this issue.</div><div><br></div><div>As a workaround for the existing installations,&nbsp;editing of the <code>proxmox_vmid</code> instance detail by users can be prevented by adding this detail name to the global configuration parameter <code>- user.vm.denied.details</code>.</div>"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://lists.apache.org/thread/n8mt5b7wkpysstb8w7rr9f02kc5cq2xm",
          "tags": [
            "vendor-advisory"
          ]
        }
      ],
      "metrics": [
        {
          "other": {
            "type": "Textual description of severity",
            "content": {
              "text": "moderate"
            }
          }
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Sander Grendelman <sander.grendelman@axians.com>",
          "type": "reporter"
        }
      ],
      "x_generator": {
        "engine": "Vulnogram 0.2.0"
      }
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  },
  "cveMetadata": {
    "cveId": "CVE-2026-25199",
    "assignerOrgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
    "serial": 1,
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}