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: cloudstack
References2
- lists.apache.org/thread/n8mt5b7wkpysstb8w7rr9f02kc5cq2xm Mailing ListThird Party Advisory
- www.openwall.com/lists/oss-security/2026/05/09/3 Mailing ListThird Party Advisory
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 1% percentile: 44 · as of 13 November 2026
- CWE
- CWE-359
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