CVE-2025-62506
MinIO vulnerable to privilege escalation via session policy bypass in service accounts and STS
Description
MinIO is a high-performance object storage system. In all versions prior to RELEASE.2025-10-15T17-29-55Z, a privilege escalation vulnerability allows service accounts and STS (Security Token Service) accounts with restricted session policies to bypass their inline policy restrictions when performing operations on their own account, specifically when creating new service accounts for the same user. The vulnerability exists in the IAM policy validation logic where the code incorrectly relied on the DenyOnly argument when validating session policies for restricted accounts. When a session policy is present, the system should validate that the action is allowed by the session policy, not just that it is not denied. An attacker with valid credentials for a restricted service or STS account can create a new service account for itself without policy restrictions, resulting in a new service account with full parent privileges instead of being restricted by the inline policy. This allows the attacker to access buckets and objects beyond their intended restrictions and modify, delete, or create objects outside their authorized scope. The vulnerability is fixed in version RELEASE.2025-10-15T17-29-55Z.
How to fix CVE-2025-62506
To remediate CVE-2025-62506, upgrade the affected package to a fixed version below.
- —upgrade to 2025.10.15 or later
- —upgrade to 0.0.0-20251015170045-c1a49490c78e or later
- —upgrade to 0.0.0-20251015170045-c1a49490c78e or later
Is CVE-2025-62506 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.