Auth bypass in Apache Cloudstack
CVE-2025-66170
The CloudStack Backup plugin has an improper authorization 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 has access to specific APIs can list backups from any account in the environment. This vulnerability does not allow them to see the contents of the backup. Users are recommended to upgrade to version 4.22.0.1, which fixes the issue.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.005 (39.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 39.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Apache Cloudstack
- Apache Software Foundation Cloudstack — versions 4.21.0.0
Weakness classification (CWE)
References
- lists.apache.org/thread/n8mt5b7wkpysstb8w7rr9f02kc5cq2xm (vendor-advisory, Mailing List, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2025-66170?
- CVE-2025-66170 is a medium-severity vulnerability in Apache Cloudstack, classified under Incorrect Authorization. CVSS score: 6.5/10. Published 2026-05-08.
- How severe is CVE-2025-66170?
- Medium severity. CVSS v3 base score is 6.5 out of 10.