Description
Account users are allowed by default to register templates to be downloaded directly to the primary storage for deploying instances using the KVM hypervisor. Due to missing file name sanitization, an attacker can register malicious templates to execute arbitrary code on the KVM hosts. This can result in the compromise of resource integrity and confidentiality, data loss, denial of service, and availability of the KVM-based infrastructure managed by CloudStack. Users are recommended to upgrade to Apache CloudStack versions 4.20.3.0 or 4.22.0.1, or later, which fixes this issue.
Affected products
apache: cloudstack
References2
- lists.apache.org/thread/n8mt5b7wkpysstb8w7rr9f02kc5cq2xm Mailing ListVendor Advisory
- www.openwall.com/lists/oss-security/2026/05/09/6
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 55 · as of 13 November 2026
- CWE
- CWE-94
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