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TI-2026-20355 Aliases CVE-2026-25199GHSA-whfq-93mc-cv6g

Apache CloudStack: Proxmox Extension Allows Unauthorized Cross-Tenant Instance Access

Priority MEDIUM 48CWE-200Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · High · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-200.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.005 43rd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ApacheApache CloudStack4.21.0 – 4.22.0—No fix listedCNA
  • Apache CloudStack VendorApache Affected 4.21.0 – 4.22.0 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:apache:cloudstack:*:*:*:*:*:*:*:*4.21.0.0 to before 4.22.0.1VulnerableApache
  • cpe:2.3:a:apache:cloudstack:*:*:*:*:*:*:*:* Versions 4.21.0.0 to before 4.22.0.1 Vulnerable ·Apache

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    Apache CloudStack — lists.apache.org/thread/n8mt5b7wkpysstb8w7rr9f02kc5cq2xm

    7 records Highest priority Priority MEDIUM 2 MEDIUM, 5 LOW

    Other records, highest priority first

    • TI-2026-20257 Apache CloudStack: Unauthenticated Command Injection in Direct Download TemplatesPriority MEDIUM 41
    • TI-2025-40697 Apache CloudStack: Any user can attach a volume in their VMs from backups they should not have access toPriority LOW 38
    • TI-2025-40894 Apache CloudStack: MinIO policy remains intact on bucket deletionPriority LOW 37
    Show all 7 records → Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-25199
  2. 2026-10-03 Alias added: GHSA-whfq-93mc-cv6g

References

Advisory 1

  • TI-2024-27459 Apache CloudStack: SAML Signature Exclusion CVSS 3.1HIGH 8.1
  • TI-2024-25607 Apache CloudStack: Unauthenticated cluster service port leads to remote execution CVSS 3.1CRITICAL 9.8
  • TI-2022-16183 Apache CloudStack SAML Single Sign-On XXE CVSS 3.1CRITICAL 9.8
  • TI-2012-03843 Citrix Cloud.com CloudStack, and Apache CloudStack pre-release, allows remote attackers… CVSS 2.0HIGH 10.0
  • TI-2024-26763 Apache CloudStack: Integration API service uses dynamic port when disabled CVSS 3.1CRITICAL 9.8
  • TI-2016-05854 Apache CloudStack 4.1 to 4.8.1.0 and 4.9.0.0 contain an API call designed to allow a user… CVSS 3.1CRITICAL 9.8
See all 64 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences