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TI-2021-04461 Aliases CVE-2021-21362

Bypassing readOnly policy by creating a temporary 'mc share upload' URL

Priority LOW 36CWE-285Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-285.

Summary

MinIO is an open-source high performance object storage service and it is API compatible with Amazon S3 cloud storage service. In MinIO before version RELEASE.2021-03-04T00-53-13Z it is possible to bypass a readOnly policy by creating a temporary 'mc share upload' URL. Everyone is impacted who uses MinIO multi-users. This is fixed in version RELEASE.2021-03-04T00-53-13Z. As a workaround, one can disable uploads with `Content-Type: multipart/form-data` as mentioned in the S3 API RESTObjectPOST docs by using a proxy in front of MinIO.

Why it matters now

EPSS 0.01321 71st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
MinIOminio< RELEASE.2021-03-04T00-53-13Z—No fix listedCNA
  • minio VendorMinIO Affected < RELEASE.2021-03-04T00-53-13Z Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:minio:minio:*:*:*:*:*:*:*:*before 2021-03-04t00-53-13zVulnerableMinIO
  • cpe:2.3:a:minio:minio:*:*:*:*:*:*:*:* Versions before 2021-03-04t00-53-13z Vulnerable ·MinIO

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Not affected: 2 products
  • Red Hat Advanced Cluster Management for Kubernetes 2
  • Red Hat Openshift Container Storage 4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-21362

References

Exploit 1

Patch 1

Advisory 2

  • TI-2023-12978 MinIO is vulnerable to privilege escalation on Linux/MacOS KEVCVSS 3.1HIGH 8.8
  • TI-2023-12976 Minio Information Disclosure in Cluster Deployment KEVCVSS 3.1HIGH 7.5
  • TI-2023-11082 Allowed DELETE on resources on object locked buckets under Governance mode in Minio CVSS 3.1HIGH 8.8
  • TI-2024-16264 MinIO unsafe default: Access keys inherit `admin` of root user, allowing privilege escalation CVSS 3.1HIGH 8.8
  • TI-2022-08654 Improper Privilege Management in MinIO CVSS 3.1HIGH 8.8
  • TI-2022-13073 Possible DDOS by establishing keep-alive connections with anonymous HTTP clients in MinIO CVSS 3.1HIGH 7.5
See all 22 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences