HPE Helion Eucalyptus v4.3.0 and earlier does not correctly check IAM user's permissions for accessing versioned objects and ACLs. In some cases, authenticated users with S3 permissions could also access versioned data.
Conclusion & alert: CVE-2016-8520 is rated Moderate Risk (56.6/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.48%).Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
Exploit prediction scoring system (EPSS) score for CVE-2016-8520
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).