CVE-2023-28434
Published: September 19, 2023
Official Description
MinIO contains a security feature bypass vulnerability that allows an attacker to use crafted requests to bypass metadata bucket name checking and put an object into any bucket while processing `PostPolicyBucket` to conduct privilege escalation. To carry out this attack, the attacker requires credentials with `arn:aws:s3:::*` permission, as well as enabled Console API access.
CISA KEV Advisory
MinIO Security Feature Bypass Vulnerability
MinIO contains a security feature bypass vulnerability that allows an attacker to use crafted requests to bypass metadata bucket name checking and put an object into any bucket while processing `PostPolicyBucket` to conduct privilege escalation. To carry out this attack, the attacker requires credentials with `arn:aws:s3:::*` permission, as well as enabled Console API access.
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Risk Analysis
MinIO contains a security feature bypass vulnerability that allows an attacker with specific credentials to bypass metadata bucket name checking and put objects into any bucket, leading to privilege escalation. The high EPSS score and confirmed exploitation by CISA indicate a critical privilege escalation risk for MinIO deployments.
This vulnerability has been actively exploited in the wild. Exploitation requires an attacker to have credentials with 'arn:aws:s3:::' permission and enabled Console API access.
MinIO users should update to a patched version that addresses this security feature bypass. Review and restrict permissions for MinIO users, ensuring the principle of least privilege is strictly followed.
Technical Analysis
CVE-2023-28434 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2023-28434 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
Exploit & PoC Resources
All References (2)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2023-28434 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1