CVE-2023-28434: MinIO Security Feature Bypass Vulnerability

High severity, CVSS 8.8. Actively exploited: in CISA KEV since 2023-09-19. EPSS: 7.9% chance of exploitation in the next 30 days.

Minio is a Multi-Cloud Object Storage framework. Prior to RELEASE.2023-03-20T20-16-18Z, an attacker can use crafted requests to bypass metadata bucket name checking and put an object into any bucket while processing `PostPolicyBucket`. To carry out this attack, the attacker requires credentials with `arn:aws:s3:::*` permission, as well as enabled Console API access. This issue has been patched in RELEASE.2023-03-20T20-16-18Z. As a workaround, enable browser API access and turn off `MINIO_BROWSER=off`.

Affected products

• MinIO MinIO: before 2023-03-20t20-16-18z (fixed in 2023-03-20t20-16-18z)

Published 2023-03-22. Last modified 2026-06-17.