CVE-2021-21362

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

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.2021-03-04T00-53-13Z 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.

Categories

7.7
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.08%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: minio minio
Published at:
Updated at:

References

Link Tags
https://github.com/minio/minio/security/advisories/GHSA-hq5j-6r98-9m8v third party advisory
https://github.com/minio/minio/pull/11682 third party advisory exploit
https://github.com/minio/minio/commit/039f59b552319fcc2f83631bb421a7d4b82bc482 third party advisory patch
https://github.com/minio/minio/releases/tag/RELEASE.2021-03-04T00-53-13Z third party advisory release notes

Frequently Asked Questions

What is the severity of CVE-2021-21362?
CVE-2021-21362 has been scored as a high severity vulnerability.
How to fix CVE-2021-21362?
To fix CVE-2021-21362, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21362 being actively exploited in the wild?
It is possible that CVE-2021-21362 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21362?
CVE-2021-21362 affects minio minio.
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