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.

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…

Vulnerability class: Broken Access Control

EPSS: 0.000 (4.4th percentile) — read the EPSS interpretation.

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.

Affected products

Apache Cloudstack
Apache Software Foundation Cloudstack — versions 4.21.0.0

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

References

security@apache.org (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.