Medium · published August 21, 2026
Authenticated pre-validation SSRF vulnerability in Apache CloudStack's template and ISO registration functionality.
When registering a template or ISO, CloudStack makes a live HTTP HEAD/GET call to determine file size for secondary storage usage-limit checks, and this happens before URL validation is performed. However, this does not pose a malicious template or ISO registration risk, as URL validation still occurs prior to the actual download by the Secondary Storage VM.This issue affects Apache CloudStack: in 4.20.3.0 and from 4.21.0.0 through 4.22.1.0.
Users are recommended to upgrade to version 4.20.3.1 or 4.22.1.1 or later, which fixes the issue.
| Product | Versions | Fixed in |
|---|---|---|
| apache/cloudstack | ≥ 4.21.0.0, < 4.22.1.1 | 4.22.1.1 |
| apache/cloudstack | all versions | — |