Skip to content
Fencer Vulns
high 8.8

CVE-2021-43858 in the critical feed json

User privilege escalation in MinIO

published 2021-12-27 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-30723

cvss
8.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
35.5%
EPSS 35.5% chance of exploitation in 30 days, percentile 98%
public exploits
0
none known

Summary

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.

Patch / fix

  • minio minio 2021-12-27t07-23-18z

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-43858 updated cvss 8.8

minio: user privilege escalation in AddUser() admin API

  • Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/search-collector-rhel9, rhacm2/assisted-installer-rhel8, rhacm2/assisted-installer-agent-rhel8, rhacm2/assisted-installer-reporter-rhel8
    affected: workaround, no fix available, no fix planned “There is a workaround for this vulnerability: Changing passwords can be disabled by adding an explicit `Deny` rule to disable the API for users.”
  • Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/search-rhel8, rhacm2/subctl-rhel9, rhacm2/thanos-rhel7, rhacm2/acm-grafana-rhel8, rhacm2/openshift-hive-rhel8, rhacm2/rcm-controller-rhel8, +21 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

35.46% chance of exploitation in the next 30 days, higher than 98% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 6.5 AV:N/AC:L/Au:S/C:P/I:P/A:P

Affected products

  • minio minio

Classification

Weakness
  • CWE-269 Improper Privilege Management
  • CWE-863 Incorrect Authorization

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.