---
id: CVE-2025-66171
title: >-
  The CloudStack Backup plugin has an improper access logic in versions 4.21.0.0
  and 4.22.0.0
summary: >-
  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 API…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-359
vendor: apache
product: cloudstack
affected:
  - 'cloudstack >= 4.21.0.0, < 4.22.0.1'
patched:
  - cloudstack 4.22.0.1
published: '2026-05-08'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T22:10:00.273'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-66171'
references:
  - url: 'https://lists.apache.org/thread/n8mt5b7wkpysstb8w7rr9f02kc5cq2xm'
    label: security@apache.org
  - url: 'http://www.openwall.com/lists/oss-security/2026/05/09/2'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.0053
epssPercentile: 0.42652
ingestedAt: '2026-09-30T22:27:27.785Z'
---

## Overview

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 create new VMs using backups of any other user of the environment.

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

- `cloudstack >= 4.21.0.0, < 4.22.0.1`

## Remediation

Upgrade past the affected range:

- `cloudstack 4.22.0.1`