CVE-2021-21362: Bypassing readOnly policy by creating a temporary 'mc share upload' URL

Published Mar 8, 2021
·
Updated

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.

Affected Software

1 affected component
MinIO<2021-03-04t00-53-13z

Event History

Mar 8, 2021
CVE Published
via MITRE·06:40 PM
Data Sourced
via MITRE·06:40 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the severity of CVE-2021-21362?

CVE-2021-21362 has been classified as a medium severity vulnerability due to the potential bypass of the readOnly policy.

2

How do I fix CVE-2021-21362?

To mitigate CVE-2021-21362, upgrade MinIO to a version later than RELEASE.2021-03-04T00-53-13Z.

3

What systems are affected by CVE-2021-21362?

CVE-2021-21362 affects all versions of MinIO prior to RELEASE.2021-03-04T00-53-13Z.

4

What vulnerability does CVE-2021-21362 address?

CVE-2021-21362 addresses the issue of bypassing a readOnly policy by creating temporary 'mc share upload' URLs.

5

Is CVE-2021-21362 related to any specific MinIO functionality?

CVE-2021-21362 is specifically related to the sharing and uploading functionality within MinIO.

Contact

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