CVEs-PoC/2021/CVE-2021-21390.md

### [CVE-2021-21390](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-21390)
![](https://img.shields.io/static/v1?label=Product&message=minio&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=%3C%20RELEASE.2021-03-17T02-33-02Z%20&color=brightgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=CWE-924%3A%20Improper%20Enforcement%20of%20Message%20Integrity%20During%20Transmission%20in%20a%20Communication%20Channel&color=brightgreen)

### Description

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.2021-03-17T02-33-02Z, there is a vulnerability which enables MITM modification of request bodies that are meant to have integrity guaranteed by chunk signatures. In a PUT request using aws-chunked encoding, MinIO ordinarily verifies signatures at the end of a chunk. This check can be skipped if the client sends a false chunk size that is much greater than the actual data sent: the server accepts and completes the request without ever reaching the end of the chunk + thereby without ever checking the chunk signature. This is fixed in version RELEASE.2021-03-17T02-33-02Z. As a workaround one can avoid using "aws-chunked" encoding-based chunk signature upload requests instead use TLS. MinIO SDKs automatically disable chunked encoding signature when the server endpoint is configured with TLS.

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/20142995/nuclei-templates
- https://github.com/cyb3r-w0lf/nuclei-template-collection