Auth bypass in Minio

CVE-2021-43858

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.

Vulnerability class: Privilege Escalation

EPSS: 0.355 (98.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

  • Minio — versions < RELEASE.2021-12-27T07-23-18Z

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-43858?
CVE-2021-43858 is a high-severity vulnerability in Minio, classified under Improper Privilege Management. CVSS score: 8.8/10. Published 2021-12-27.
How severe is CVE-2021-43858?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2021-43858 known to be exploited?
12 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.