CVE-2025-66172: Apache CloudStack: Any user can attach a volume in their VMs from backups they should not have access to

Severity: high (CVSS 8.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-08 · updated 2026-10-07
Weakness: CWE-359

Description

The CloudStack Backup plugin has an improper access logic in versions 4.21.0.0 and 4.22.0.0. Anyone with authenticated user-account access in CloudStack 4.21.0.0+ environments, where this plugin is enabled and have access to specific APIs can restore a volume from any other user's backups and attach the volume to their own VMs. Backup plugin users using CloudStack 4.21.0.0+ are recommended to upgrade to CloudStack version 4.22.0.1, which fixes this issue.

Affected products

Apache Software Foundation Apache CloudStack: from 4.21.0.0 before 4.22.0.1 — fixed in 4.22.0.1

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache CloudStack 4.22.0.1. Check the vendor advisory for mitigations.

References

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