CVE-2021-21390 MITM modification of request bodies in MinIO
Attackers can modify request bodies during transmission by bypassing chunk signature verification in MinIO object storage.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-21390?
CVE-2021-21390 is a medium-severity vulnerability in minio, published on 19 Mar 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-924
Which versions are affected by CVE-2021-21390?
It affects 1 product.
Products include Minio Minio.
How do I fix CVE-2021-21390?
Upgrade to a fixed version.
Is CVE-2021-21390 being exploited?
There is no known exploitation of CVE-2021-21390 in the wild and no public exploit code.
Other vulnerabilities in minio
Sources
Also known as GHSA-xr7r-7gpj-5pgp, MINI-hm38-f53w-6r44, MINI-w4qj-66qm-r7xw.