CVE-2021-43858: MinIO

High severity, CVSS 8.8. EPSS: 35.5% chance of exploitation in the next 30 days.

MinIO is a Kubernetes native application for cloud storage. Prior to version `RELEASE.2021-12-27T07-23-18Z`, a malicious client can hand-craft an HTTP API call that allows for updating policy for a user and gaining higher privileges. The patch in version `RELEASE.2021-12-27T07-23-18Z` changes the accepted request body type and removes the ability to apply policy changes through this API. There is a workaround for this vulnerability: Changing passwords can be disabled by adding an explicit `Deny` rule to disable the API for users.

Affected products

• MinIO MinIO: before 2021-12-27t07-23-18z (fixed in 2021-12-27t07-23-18z)

Published 2021-12-27. Last modified 2026-06-17.