{"id":"CVE-2021-21362","aliases":["EUVD-2021-8679","GHSA-hq5j-6r98-9m8v"],"status":"published","title":"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.","severity":{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.01321,"percentile":0.71297,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-285","CWE-863"],"published":"2021-03-08T18:40:34Z","modified":"2026-10-20T10:54:28Z","products":[{"vendor":"minio","product":"minio"}],"references":[{"url":"https://github.com/minio/minio/security/advisories/GHSA-hq5j-6r98-9m8v","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory","advisory"]},{"url":"https://github.com/minio/minio/pull/11682","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","evidence"]},{"url":"https://github.com/minio/minio/commit/039f59b552319fcc2f83631bb421a7d4b82bc482","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix"]},{"url":"https://github.com/minio/minio/releases/tag/RELEASE.2021-03-04T00-53-13Z","tags":["x_refsource_MISC","x_transferred","Release Notes","Third Party Advisory","advisory"]}],"sources":{"cve":[{"id":"CVE-2021-21362","title":"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.","status":"published","published":"2021-03-08T18:40:34Z","modified":"2024-08-03T18:09:15.715Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-285"],"updated_at":"2026-11-02T14:33:00.137099Z"}],"euvd":[{"id":"EUVD-2021-8679","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.","status":"published","published":"2021-03-08T18:40:34Z","modified":"2024-08-03T18:09:15Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N","level":"high"}],"updated_at":"2026-11-03T03:25:06.347262Z"}],"nvd":[{"id":"CVE-2021-21362","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.","status":"published","published":"2021-03-08T19:15:13.443Z","modified":"2026-06-17T03:35:23.51Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N","level":"high","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":4,"vector":"AV:N/AC:L/Au:S/C:N/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-285","CWE-863"],"updated_at":"2026-11-02T14:06:50.399901Z"}],"osv":[{"id":"CVE-2021-21362","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.","status":"published","published":"2021-03-08T19:15:13.443Z","modified":"2026-10-20T10:54:28.37157441Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:18.004149Z"}]}}