CVE-2021-43858 User privilege escalation in MinIO

What is CVE-2021-43858?

CVE-2021-43858 is a high-severity vulnerability in minio, published on 27 Dec 2021. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

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.

Weakness: CWE-863, CWE-269

Which versions are affected by CVE-2021-43858?

It affects 1 product.

Products include Minio Minio.

How do I fix CVE-2021-43858?

Upgrade to a fixed version.

Is CVE-2021-43858 being exploited?

There is no known exploitation of CVE-2021-43858 in the wild and no public exploit code.

Public exploit code: 2 proofs of concept on GitHub.

Other vulnerabilities in minio

• CVE-2023-28434 MinIO Security Feature Bypass Exploited High 8.8
• CVE-2023-28432 MinIO Information Disclosure Exploited High 7.5
• CVE-2020-11012 Authentication bypass MinIO Admin API Critical 9.3
• CVE-2026-33322 MinIO: JWT Algorithm Confusion in OIDC Authentication Critical 9.2
• CVE-2026-33419 MinIO: LDAP login brute-force via user enumeration and missing rate limit Critical 9.1

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-j6jc-jqqc-p6cx, MINI-2mgh-r4pj-945h, MINI-g8g3-mpv9-6rfw.